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 Talk Talk - Communication terms
Category: General technical and industrial
Date & country: 28/05/2010, UK
Words: 18630


Andorra la Vella
Capital of the principality of Andorra; population (2003 est) 23,400. It is in the Gran Valira valley, on the eastern slopes of the Pic d'Enclar, in the Pyrenees, at 1,029 m/3,376 ft. It is the principality's only city and its chief centre of trade, commerce, and manufacturing. Its main sources of income are tourism, duty-free i...

antonym
Word that is opposite in meaning to another word. The following are antonyms: good and evil; slow and fast; hot and cold. There are three different types of antonym: gradable, complementary, and converse. Gradable antony...

Anglo-Irish War
Conflict in Ireland 1919–21, between the Irish Republican Army (IRA), the paramilitary wing of Sinn Fein, and British government forces, reinforced by the ex-service Auxiliaries and Black and Tans. Its outbreak is usually dated to the IRA's killing of two policemen in Soloheadbeg, County Tipperary, on 21 January 1919. Following a war o...

Anglo-Irish Treaty
In Irish history, articles of agreement between Britain and southern Ireland signed in London in December 1921, which confirmed the end of the Anglo-Irish War (1919–21) but then precipitated the Irish Civil War (1922–23). The settlement created the Irish Free State within the British Commonwealth and endorsed the creation of Northern ...

Anglo–Irish relations
War, diplomacy, and accord have marked relations between the UK and Ireland in the 20th century. In 1900 the island of Ireland was governed by the British government at Westminster as an integral part of the UK. By the end of the century only Northern Ireland (6 of Ireland's traditional 32 counties) remained in the UK, the majority of Ireland h...

analysis
(communication) Means of communication that involves explanation. Analysis is particularly concerned with reasoning (why something happens, be it a scientific phenomena or human behaviour). The language used to analyse scientifically must be precise and factual, whereas the language used to an...

animal cell
Cell in an animal, which, like all eukaryotic cells, has a cell membrane, cytoplasm, and a nucleus, but in which the surface consists of the cell surface membrane only – it does not have a cell wall. The cell surface membrane keeps the cell together by being strong, even though it is very thin a...

Antwerpen
Alternative name for Antwerp, a port and province in Belgium

anointing of the sick
In the Roman Catholic, Orthodox, and some Anglican churches, sacrament received in preparation for death. The recipient is anointed with holy oil by a priest. If they recover they can be anointed again on another occasion. The last rites are given to symbolize forgiveness of sins, healing of the mind, and strengthening of the spirit

anaerobic respiration
In plant and animal cells, a process in which energy is released from food molecules such as glucose without requiring oxygen. Some aerobic plants and animals are able to use anaerobic respiration for short periods of time. For example, during a sprint, human muscles can respire anaerobically. Unfortunately, lactic acid is produced and accumulates ...

Anandpur Sahib
Sikh religious site renowned for being the birthplace of the Khalsa, the Panj Pyares, the five faithful ones, initiated here in 1699. The site is 75 km/47 mi from the Punjab capital of Chandigarh. Guru Gobind Singh spent much of his life here. Starting his project in 1689, Guru Gobind Singh constructed five forts at Anandpur Sahib, which were l...

Aoraki
Highest point, 3,764 m/12,349 ft, of the Southern Alps, a range of mountains running through New Zealand

aorta
The body's main artery, arising from the left ventricle of the heart in birds and mammals. Carrying freshly oxygenated blood, it arches over the top of the heart and descends through the trunk, finally splitting in the lower abdomen to form the two iliac arteries. Arteries branching off the arch of the aorta carry blood to the upper body. Loss ...

Aouita, Said
Moroccan runner. Outstanding at middle and long distances, he won the 1984 Olympic and 1987 World Championship 5,000-metre titles, and has set many world records. In Rome, Italy, in 1987, he became the first person to run the 5,000 metres in under 13 minutes. Career highlights Olympic Games gold 5,000 metres 1984; bronze 800 metres 1988 Wor...

AOL
Abbreviation for America Online

Apulia
Region of Italy, in the southeast `heel`, comprising the provinces of Bari, Brindisi, Foggia, Lecce, and Taranto; area 19,362 sq km/7,476 sq mi; population (2001 est) 3,983,500. Apulia borders the Adriatic Sea in the east and the Strait of Otranto in the south; the capital is Bari, and the main industrial centre is Taranto

apricot
Yellow-fleshed fruit of the apricot tree, which is closely related to the almond, peach, plum, and cherry. Although native to the Far East, it has long been cultivated in Armenia, from where it was introduced into Europe and the USA. (Genus Prunus armeniaca, family Rosaceae.)

apple
Fruit of several species of apple tree. There are several hundred varieties of cultivated apples, grown all over the world, which may be divided into eating, cooking, and cider apples. All are derived from the wild crab apple. (Genus Malus, family Rosaceae.) Apple trees grow best in temperate countries with a cool climate and ple...

Apennines
Chain of mountains stretching the length of the Italian peninsula. It extends around 840 mi/1,350 km south from the Cadibona pass in the northwestern Liguria region. An older and more weathered continuation of the Maritime Alps, from Genoa the Apennines swing across the peninsula to Ancona on the east coast, and then back to the west coast and ...

Apollo asteroid
Member of a group of asteroids whose orbits cross that of the Earth. They are named after the first of their kind, Apollo, to be discovered. Apollo was discovered in 1932 by German astronomer Karl Reinmuth and then lost until 1973. Apollo asteroids are so small and faint that they are difficult to see except when close to the Earth (Apollo is about...

apatosaurus
Large plant-eating dinosaur, formerly called brontosaurus, which flourished about 145 million years ago. Up to 21 m/69 ft long and 30 tonnes in weight, it stood on four elephantlike legs and had a long tail, long neck, and small head. It probably snipped off low-growing vegetation with peglike front teeth, and swallowed it whole to be g...

ape
Primate of the family Pongidae, closely related to humans, including gibbon, orang-utan, chimpanzee, and gorilla. The earliest known ape is believed by US researchers to have lived 20 million yeas ago in Uganda. Morotopithecus was about the size of a modern chimpanzee

apostrophe
(grammar) Punctuation mark (') used in written English and some other languages. In English it serves primarily to indicate either a missing letter (mustn't for must not) or number ('47 for 1947), or gramma...

application
(computing) In computing, program or job designed for the benefit of the end user. Examples of general-purpose application programs include word processors, desktop publishing programs, databases, spreadsheet packages, and graphic...

Apuleius, Lucius
Roman lawyer, philosopher, and writer. He was the author of The Golden Ass, or Metamorphoses, a prose fantasy. Born at Madaura in North Africa, he was educated at Carthage and Athens. He travelled extensively in the East in order to become an initiate of religious mysteries, and then practised for some time as ...

appendicitis
Inflammation of the appendix, a small, blind extension of the bowel in the lower right abdomen. In an acute attack, the pus-filled appendix may burst, causing a potentially lethal spread of infection. Treatment is by removal (appendicectomy)

Apollo
Click images to enlargeIn Greek and Roman mythology, the god of sun, music, poetry, prophecy, agriculture, and pastoral life, and leader of the Muses. He was the twin child (with Artemis) of Zeus and Leto. Ancient statues show Apollo as the embodiment of the Greek ideal of male beauty. His chief cult centres were his supp...

Apis
Ancient Egyptian deity, a manifestation of the creator god Ptah of Memphis, in the form of a black bull with a small white triangle on the forehead, often bearing a Sun-disc between its horns. The cult of Apis originated in the early 3rd millennium BC. Apis was a fertility god, associated also with Osiris and Sokaris, gods of the dead and the u...

Aphrodite
In Greek mythology, the goddess of love (Roman Venus, Phoenician Astarte, Babylonian Ishtar). She is said to be either a daughter of Zeus (in Homer) or sprung from the foam of the sea (in Hesiod). She was the unfaithful wife of Hephaestus, the god of fire, and the mother of Eros

aphasia
General term for the many types of disturbance in language that are due to brain damage, especially in the speech areas of the dominant hemisphere

apartheid
Racial-segregation policy of the government of South Africa from 1948 to 1994. Under the apartheid system, non-whites – classified as Bantu (black), coloured (mixed), or Indian – did not share full rights of citizenship with the white minority. For example, black people could not vo...

Apache
Member of an American Indian people who migrated from Canada to Arizona, and parts of Colorado, New Mexico, Texas, and north Mexico, between AD 850 and 1400. The Apache language belongs to the Athabaskan linguistic group, through which they are related to the neighbouring Navajo. Buffalo hunting and ...

Appomattox Court House
Former town in Virginia, USA, scene of the surrender on 9 April 1865 of the Confederate army under Robert E Lee to the Union army under Ulysses S Grant, which ended the American Civil War. The house where the surrender was signed is now a museum, 5 km/3 mi from the modern town of Appomattox

appeasement
Historically, the conciliatory policy adopted by the British government, in particular under Neville Chamberlain, towards the Nazi and fascist dictators in Europe in the 1930s in an effort to maintain peace. It was strongly opposed by Winston Churchill, but the Munich Agreement of 1938 was almost universally hailed as its justification. Appeasement...

Appalachian Mountains
Mountain system in eastern North America, stretching about 2,400 km/1,500 mi from Alabama to Québec. The chain, composed of ancient eroded rocks and rounded peaks, includes the Allegheny, Catskill, and Blue Ridge mountains. Its width in some parts reaches 500 km/311 mi. Mount Mitchell, i...

apostolic succession
Doctrine in the Christian church that certain spiritual powers were received by the first apostles directly from Jesus, and have been handed down in the ceremony of `laying on of hands` from generation to generation of bishops

apostle
In the New Testament, any of the chosen 12 disciples sent out by Jesus, after his resurrection, to preach the gospel. In the earliest days of Christianity, the term was extended to include some who had never known Jesus in the flesh, notably St Paul. The qualifications for an apostle, in the full sen...

Apollinaire, Guillaume
French poet of aristocratic Polish descent. He was a leader of the avant-garde in Parisian literary and artistic circles. His novel Le Poète assassiné/The Poet Assassinated (1916), followed by the experimental poems Alcools/Alcohols (1913) and Calligrammes/Word Pictures
aphrodisiac
Any substance that arouses or increases sexual desire

Apia
Capital and chief port of Samoa, on the north coast of Upolu; population (2001) 38,800. Copra, bananas, and cocoa beans are exported. There is a high-power radio communication station and an observatory. The town is built on a curving bay, backed by a conical hill, Vaea, beyond which is a mountain range. Foreign consulates were set up in Ap...

Apollonius of Rhodes
Greek poet. He was the author of the epic Argonautica, which tells the story of Jason and the Argonauts and their quest for the Golden Fleece. A pupil of Callimachus, he was for a time head of the library at Alexandria. Apollonius was innovative in making Medea's love for Jason an integral part of his story. It is likely that...

Appleton layer
Band containing ionized gases in the Earth's upper atmosphere, at a height of 150–1,000 km/94–625 mi, above the E-layer (formerly the Kennelly-Heaviside layer). It acts as a dependable reflector of radio signals as it is not affected by atmospheric conditions, although its ionic composition varies with the sunspot cycle. T...

aperture
In photography, an opening in the camera that allows light to pass through the lens to strike the film. Controlled by the iris diaphragm, it can be set mechanically or electronically at various diameters. The aperture ratio or relative aperture, more commonly known as the f-number, is a number defined as the focal length of the lens divided by ...

aphid
Any of the family of small insects, Aphididae, in the order Hemiptera, suborder Homoptera, that live by sucking sap from plants. There are many species, often adapted to particular plants; some are agricultural pests. In some stages of their life cycle, wingless females rapidly produce large numbers of live young by parthenogenesis, leading to ...

Apocrypha
Appendix to the Old Testament of the Bible, 14 books not included in the final Hebrew canon but recognized by Roman Catholics. There are also disputed New Testament texts known as Apocrypha

appliqué
Embroidery used to create pictures or patterns by `applying` pieces of material onto a background fabric. The pieces are cut into the appropriate shapes and sewn on, providing decoration for wall hangings, furnishing textiles, and clothes

Apostles' Creed
In the Christian church, the oldest of the creeds (Latin credo `I believe`), a list of important Christian beliefs. A 4th-century legend states that it was composed by the 12 apostles, but it is generally agreed that the Apostles' Creed was only based on their teachings. Most of the Creed was written in the 2nd ...

apatite
Common calcium phosphate mineral, Ca5(PO4)3(F,OH,Cl). Apatite has a hexagonal structure and occurs widely in igneous rocks, such as pegmatite, and in contact metamorphic rocks, such as marbles. It is used in the manufacture of fertilizer and as a source of phosphorus. Carbonate hy...

aphelion
Point at which an object, travelling in an elliptical orbit around the Sun, is at its farthest from the Sun. This is a solar-orbit apoapsis. The Earth is at its aphelion on 5 July

apogee
Point at which a spacecraft, or other object, travelling in an elliptical orbit around the Earth is at its farthest from the Earth. This is an Earth-orbit apoapsis

Apelles
Greek painter, one of the most celebrated of antiquity. No trace of his work, which was praised for its startling realism, now remains. He was court artist to Philip II of Macedon and then to Alexander the Great, whose portrait Apelles alone was allowed to paint. Apelles studied in the studio of the Greek painter Pamphilos (fl. c....

Apo, Mount
Active volcano and highest peak in the Philippines, rising to 2,954 m/9,692 ft on the island of Mindanao

apothecaries' weights
Obsolete units of mass, formerly used in pharmacy: 20 grains equal one scruple; three scruples equal one dram; eight drams equal an apothecary's ounce (oz apoth.), and 12 such ounces equal an apothecary's pound (lb apoth.). There are 7,000 grains in one pound avoirdupois (0.454 kg)

Apollonius of Perga
Greek mathematician, called `the Great Geometer`. In his work Konica/The Conics he showed that a plane intersecting a cone will generate an ellipse, a parabola, or a hyperbola, depending on the angle of intersection. In astronomy, he used a system of circles called epicycles and deferents to explain the motion of th...

appendix
(anatomy) Short, blind-ended tube attached to the caecum. It has no known function in humans, but in herbivores it may be large, containing millions of bacteria that secrete enzymes to digest grass (as no vertebrate can secrete en...

apparent depth
Depth that a transparent material such as water or glass appears to have when viewed from above. This is less than its real depth because of the refraction that takes place when light passes into a less dense medium. The ratio of the real depth to the apparent depth of a transparent material is equal...

appeal
In law, an application for a rehearing of all or part of an issue that has already been dealt with by a lower court or tribunal. The outcome can be a new decision on all or part of the points raised, or the previous decision may be upheld. In criminal cases, an appeal may be against conviction and either the prosecution or the defence may appeal ag...

appropriate technology
Simple or small-scale machinery and tools that, because they are cheap and easy to produce and maintain, may be of most use in the developing world; for example, hand ploughs and simple looms. This equipment may be used to supplement local crafts and traditional skills to encourage small-scale industrialization. Many countries suffer fr...

approximation
Rough estimate of a given value. For example, for pi (which has a value of 3.1415926 correct to seven decimal places), 3 is an approximation to the nearest whole number

APR
Abbreviation for annual percentage rate

aphorism
Short, sharp, witty saying, usually making a general observation. `Experience is the name everyone gives to their mistakes` is one of many aphorisms by Irish playwright Oscar Wilde. The term derives from the Aphorisms ascribed to Greek writer Hippocrates. An aphorism which has become universally accepted is a proverb

apposition
In grammar, the placing of a noun or noun phrase next to another that refers to the same thing (`We'll take the easiest route, the east ridge, to the top`). The word or phrase in apposition is marked off from its antecedent (to which it refers) by a pair of commas

Appennino
Italian name for the Apennines, a chain of mountains stretching the length of the Italian peninsula

aqueduct
Click images to enlargeAny artificial channel or conduit for water, originally applied to water supply tunnels, but later used to refer to elevated structures of stone, wood, or iron carrying navigable canals across valleys. One of the first great aqueducts was built in 691 BC, carrying water for 80 km/50 mi to Nineva...

aqualung
Underwater breathing apparatus worn by divers, developed in the early 1940s by French diver Jacques Cousteau. Compressed-air cylinders strapped to the diver's back are regulated by a valve system and by a mouth tube to provide air to the diver at the same pressure as that of the surrounding water (which increases with the depth)

Aquitaine
Region of southwest France; administrative capital Bordeaux; area 41,308 sq km/15,949 sq mi; population (1999 est) 2,908,400. It comprises the départements of Dordogne, Gironde, Landes, Lot-et-Garonne, and Pyrénées-Atlantiques. The climate is extremely wet. Red wines (Margaux, St Julien)...

Aquila
Constellation on the celestial equator (see celestial sphere). Its brightest star is first-magnitude Altair, flanked by the stars Beta and Gamma Aquilae. It is represented by an eagle. Nova Aquilae, which appeared June 1918, shone for a few days nearly as brightly as Sirius

Aquarius
Zodiacal constellation a little south of the celestial equator near Pegasus. Aquarius is represented as a man pouring water from a jar. The Sun passes through Aquarius from late February to early March. In astrology, the dates for Aquarius, the 11th sign of the zodiac, are between about 20 January and 18 February (see precession)

aqueous humour
Watery fluid found in the chamber between the cornea and lens of the vertebrate eye. Similar to blood serum in composition, it is constantly renewed

aquarium
Tank or similar container used for the study and display of living aquatic plants and animals. The same name is used for institutions that exhibit aquatic life. These have been common since Roman times, but the first modern public aquarium was opened in Regent's Park, London, in 1853. A recent development is the oceanarium or seaquarium, a larg...

aquaplaning
Phenomenon in which the tyres of a road vehicle cease to make direct contact with the road surface, owing to the presence of a thin film of water. As a result, the vehicle can go out of control, particularly if the steered wheels are involved

aquifer
A body of rock through which appreciable amounts of water can flow. The rock of an aquifer must be porous and permeable (full of interconnected holes) so that it can conduct water. Aquifers are an important source of fresh water, for example for drinking and irrigation, in many arid areas of the world, and are exploited by the use of artesian wells...

aquamarine
Blue variety of the mineral beryl. A semi-precious gemstone, it is used in jewellery

Aquinas, St Thomas
Italian philosopher and theologian, the greatest figure of the school of scholasticism. He was a Dominican monk, known as the `Angelic Doctor`. In 1879 his works were recognized as the basis of Catholic theology. His Summa contra Gentiles/Against the Errors of the Infidels (1259–64) argues that reason and faith...

Aqtöbe
(city) Industrial city on the River Ilek, in northwestern Kazakhstan, 100 km/62 mi south of the border with the Russian Federation, capital of Aqtöbe oblast (region); population (2004) 249,800. Chemicals, metals, electrical equipment are among the goods manufactured here. Aqtö...

Aqaba, Gulf of
Gulf extending northwards from the Red Sea for 160 km/100 mi to the Negev; its coastline is uninhabited except at its head, where the frontiers of Israel, Egypt, Jordan, and Saudi Arabia converge. The two ports of Elat and Aqaba, Jordan's only port, are situated here

aquatint
Printmaking technique. When combined with etching it produces areas of subtle tone as well as more precisely etched lines. Aquatint became common in the late 18th century. An etching plate is covered with a fine layer of resin and then immersed in acid, which bites through the resin, causing tiny pits on the surface of the plate. When printed, a fi...

Aquino,
(Maria) Filipino centrist politician, president 1986–92. She was instrumental in the nonviolent overthrow of President Ferdinand Marcos in 1986. As president, she sought to rule in a conciliatory manner, but encountered opposition from the left (communist guerrillas) and the right (army c...

aquaculture
Click images to enlargeThe cultivation of fish and shellfish for human consumption; see fish farming

aquatic insect
Insect that spends all or part of its life in water. Of the 29 insect orders, 11 members have some aquatic stages. Most of these have aquatic, immature stages, which usually take place in fresh water, sometimes in brackish water (very few species are truly marine); the adults are terrestrial, but in some orders there are species where all stage...

arrowroot
Starchy substance used as a thickener in cooking, produced from the clumpy roots of various tropical plants. The true arrowroot (Maranta arundinacea) was used by native South Americans as an antidote against the effects of poisoned arrows. The West Indian island of St Vincent is the main source of supply today. The plant roots an...

araucaria
Coniferous tree related to the firs, with flat, scalelike needles. Once widespread, it is now native only to the southern hemisphere. Some grow to gigantic size. Araucarias include the monkey-puzzle tree (Araucaria araucana), the Australian bunya bunya pine (A. bidwillii), and the Norfolk Island pine (
Aries
Zodiacal constellation in the northern hemisphere between Pisces and Taurus, near Auriga, represented as the legendary ram whose golden fleece was sought by Jason and the Argonauts. Its most distinctive feature is a curve of three stars of decreasing brightness. The brightest of these is Hamal or Alpha Arietis, 65 light years from Earth. The Sun pa...

areca
Any of a group of palm trees native to Asia and Australia. The betel nut comes from the species Areca catechu. (Genus Areca.)

Ariane rocket
Series of launch vehicles built by the European Space Agency, mainly to put telecommunications satellites into orbit two at a time. The first flight was in 1979. The launch site is the Centre Spatial Guyanais, at Kourou in French Guiana. Ariane is a three-stage rocket using liquid fuels. Small so...

Arcturus
Brightest star in the constellation Boötes and the fourth-brightest star in the night sky. Arcturus is a red giant about 28 times larger than the Sun and 70 times more luminous, 36 light years away from the Sun

arc minute
Unit for measuring small angles, used in geometry, surveying, map-making, and astronomy. An arc minute is one-sixtieth of a degree and is divided into 60 arc seconds (symbol "). Small distances in the sky, as between two close stars or the apparent width of a planet's disc, are expressed in minutes and seconds of arc

arsenic
Semimetallic element (a metalloid), atomic number 33, relative atomic mass 74.92. Like phosphorus, the element can appear in different modifications, of which the grey, `metallic` arsenic is the most stable. Arsenic occurs in many ores and occasionally in its elemental state, and is widely distributed, being present in minute quantities i...

argon
Colourless, odourless, non-metallic, gaseous element, atomic number 18, relative atomic mass 39.948. It is grouped with the noble gases (rare gases) in Group 0 of the periodic table of the elements. It was long believed not to react with other substances, but observations now indicate that it can be made to combine with boron fluoride to form c...

Armstrong, Neil Alden
US astronaut. On 20 July 1969, he became the first person to set foot on the Moon and made his now famous remark, `That's one small step for man, one giant leap for mankind.` The Moon landing was part of the Apollo project. He joined the US National Aerospace Program in 1962, and commanded Gemini 8...

artificial selection
In biology, selective breeding of individuals that exhibit the particular characteristics that a plant or animal breeder wishes to develop. In plants, desirable features might include resistance to disease, high yield (in crop plants), or attractive appearance. In animal breeding, selection has led to the development of particular breeds of cattle ...

arthropod
Member of the phylum Arthropoda; an invertebrate animal with jointed legs and a segmented body with a horny or chitinous casing (exoskeleton), which is shed periodically and replaced as the animal grows. Included are arachnids such as spiders and mites, as well as crustaceans, millipedes, centipedes, and insects

Archaea
Group of micro-organisms that are without a nucleus and have a single chromosome. They are now known to constitute a separate domain in the tree of life, next to and equally distant from bacteria and eukaryotes. All are strict anaerobes, that is, they are killed by oxygen. This is thought to be a primitive condition and to indicate that Archaea...

area
Size of a surface. It is measured in square units, usually square centimetres (cm2), square metres (m2), or square kilometres (km2). Surface area is the area of the outer surface of a solid. Integration may be used to determine the area of shapes enclosed by curves. The areas of t...

arc
In geometry, a section of a curved line or circle. A circle has three types of arc: a semicircle, which is exactly half of the circle; minor arcs, which are less than the semicircle; and major arcs, which are greater than the semicircle. An arc of a circle is measured in degrees, according to the angle formed by joining its two ends to ...

arithmetic progression
Sequence of numbers or terms that have a common difference between any one term and the next in the sequence. For example, 2, 7, 12, 17, 22, 27, ... is an arithmetic sequence with a common difference of 5. The nth term in any arithmetic progression can be found using the formula: nth term = a&l...

artesian well
Well that is supplied with water rising naturally from an underground water-saturated rock layer (aquifer). The water rises from the aquifer under its own pressure. Such a well may be drilled into an aquifer that is confined by impermeable rocks both above and below. If the water table (the top o...

arête
Click images to enlargeSharp narrow ridge separating two glacial troughs (U-shaped valleys), or corries. They are formed by intense freeze–thaw weathering on the sides of mountains. The typical U-shaped cross-sections of glacial troughs give arêtes very steep sides. Arêtes are common in glaciate...

archipelago
Group of islands, or an area of sea containing a group of islands. The islands of an archipelago are usually volcanic in origin, and they sometimes represent the tops of peaks in areas around continental margins flooded by the sea. Volcanic islands are formed either when a hot spot within the Earth's mantle produces a chain of volcanoes on the ...

Archaean
Widely used term for the earliest era of geological time; the first part of the Precambrian Eon, spanning the interval from the formation of Earth to about 2,500 million years ago