Spinel, Spinelle Spi·nel", Spi·nelle" noun [ French spinelle , or Late Latin spinellus , perhaps from Latin spina a thorn, a prickle, in allusion to its pointed crystals.] (Min.) A mineral occuring in octahedrons of great hardness and various colors, as red, green, blue, brown, and black, the red variety being the gem spinel ruby. It consist essentially of alumina and magnesia, but commonly contains iron and sometimes also chromium. » The spinel group includes spinel proper, also magnetite, chromite, franklinite, gahnite, etc., all of which may be regarded as composed of a sesquioxide and a protoxide in equal proportions.

Spineless Spine"less adjective Having no spine.

Spinescence Spi·nes"cence noun The state or quality of being spinescent or spiny; also, a spiny growth or covering, as of certain animals.

Spinescent Spi·nes"cent adjective [ Latin spinescens , -entis , present participle of spinescere to know to grow thorny, from spina a thorn: confer French spinescent .] (Botany) Becoming hard and thorny; tapering gradually to a rigid, leafless point; armed with spines. Gray.

Spinet Spin"et noun [ Old French espinete , French épinette (cf. Italian spinetta ), from Latin spina a thorn; -- so called because its quills resemble thorns. See Spine .] (Mus.) A keyed instrument of music resembling a harpsichord, but smaller, with one string of brass or steel wire to each note, sounded by means of leather or quill plectrums or jacks. It was formerly much used. Dumb spinet . (Mus.) See Manichordon .

Spinet Spi"net noun [ Latin spinetum . See Spinny .] A spinny. [ Obsolete] B. Jonson.

Spinetail Spine"tail` noun (Zoology) (a) Any one or several species of swifts of the genus Acanthylis , or Chætura , and allied genera, in which the shafts of the tail feathers terminate in rigid spines. (b) Any one of several species of South American and Central American clamatorial birds belonging to Synallaxis and allied genera of the family Dendrocolaptidæ . They are allied to the ovenbirds. (c) The ruddy duck. [ Local, U.S.]

Spineted Spin"et·ed adjective Slit; cleft. [ Obsolete & R.]

Spini-spirulate Spin`i-spir"u·late adjective (Zoology) Having spines arranged spirally. See Spicule .

Spiniferous Spi·nif"er·ous adjective [ Latin spinifer ; spina thorn + ferre to produce.] Producing spines; bearing thorns or spines; thorny; spiny.

Spinifex Spin"i·fex noun [ New Latin ; Latin spina spine + facere to make.] 1. (Botany) A genus of chiefly Australian grasses, the seeds of which bear an elastic spine. S. hirsutus (black grass) and S. longifolius are useful as sand binders. S. paradoxus is a valuable perennial fodder plant. Also, a plant of this genus. 2. Any of several Australian grasses of the genus Tricuspis , which often form dense, almost impassable growth, their leaves being stiff and sharp-pointed.

Spiniform Spin"i·form adjective Shaped like a spine.

Spinigerous Spi·nig"er·ous adjective [ Latin spiniger ; spina spine + gerere to bear.] Bearing a spine or spines; thorn-bearing.

Spininess Spin"i·ness noun Quality of being spiny.

Spink Spink (spĭnk) noun [ Confer dial. Swedish spink a kind of small bird, Greek spi`ggos , and English finch .] (Zoology) The chaffinch.

Spinnaker Spin"na·ker noun (Nautical) A large triangular sail set upon a boom, -- used when running before the wind.

Spinner Spin"ner noun 1. One who, or that which, spins one skilled in spinning; a spinning machine. 2. A spider. "Long-legged spinners ." Shak. 3. (Zoology) A goatsucker; -- so called from the peculiar noise it makes when darting through the air. 4. (Zoology) A spinneret. Ring spinner , a machine for spinning, in which the twist, given to the yarn by a revolving bobbin, is regulated by the drag of a small metal loop which slides around a ring encircling the bobbin, instead of by a throstle.

Spinneret Spin"ner·et noun (Zoology) One of the special jointed organs situated on the under side, and near the end, of the abdomen of spiders, by means of which they spin their webs. Most spiders have three pairs of spinnerets, but some have only two pairs. The ordinary silk line of the spider is composed of numerous smaller lines jointed after issuing from the spinnerets.

Spinnerule Spin"ner·ule noun (Zoology) One of the numerous small spinning tubes on the spinnerets of spiders.

Spinney Spin"ney noun ; plural Spinneys Same as Spinny . T. Hughes.

Spinning Spin"ning adjective & noun from Spin . Spinning gland (Zoology) , one of the glands which form the material for spinning the silk of silkworms and other larvæ. -- Spinning house , formerly a common name for a house of correction in England, the women confined therein being employed in spinning. -- Spinning jenny (Machinery) , an engine or machine for spinning wool or cotton, by means of a large number of spindles revolving simultaneously. -- Spinning mite (Zoology) , the red spider. -- Spinning wheel , a machine for spinning yarn or thread, in which a wheel drives a single spindle, and is itself driven by the hand, or by the foot acting on a treadle.

Spinny Spin"ny noun ; plural Spinnies . [ Old French espinaye , espinoye , espinei , espanoi , French épinaie , from Latin spinetum a thicket of thorns, from spina a thorn. See Spine .] A small thicket or grove with undergrowth; a clump of trees. [ Written also spinney , and spinny .]

The downs rise steep, crowned with black fir spinnies .

C. Kingsley.

Spinny Spin"ny adjective [ Confer Spiny , adjective ] Thin and long; slim; slender. [ Obsolete or Prov. Eng.]

Spinose Spi·nose" adjective [ Latin spinosus , from spina a thorn.] Full of spines; armed with thorns; thorny.

Spinosity Spi·nos"i·ty noun The quality or state of being spiny or thorny; spininess.

Spinous Spi"nous adjective 1. Spinose; thorny. 2. Having the form of a spine or thorn; spinelike. Spinous process of a vertebra (Anat.) , the dorsal process of the neural arch of a vertebra; a neurapophysis.

Spinozism Spi·no"zism noun The form of Pantheism taught by Benedict Spinoza , that there is but one substance, or infinite essence, in the universe, of which the so- called material and spiritual beings and phenomena are only modes, and that one this one substance is God. [ Written also Spinosism .]

Spinozist Spi·no"zist noun A believer in Spinozism.

Spinster Spin"ster noun [ Spin + - ster .] 1. A woman who spins, or whose occupation is to spin.

She spake to spinster to spin it out.

Piers Plowman.

The spinsters and the knitters in the sun.

Shak. 2. A man who spins. [ Obsolete] Shak. 3. (Law) An unmarried or single woman; -- used in legal proceedings as a title, or addition to the surname.

If a gentlewoman be termed a spinster , she may abate the writ.

Coke. 4. A woman of evil life and character; -- so called from being forced to spin in a house of correction. [ Obsolete]

Spinstress Spin"stress noun A woman who spins. T. Brown.

Spinstry Spin"stry noun The business of one who spins; spinning. [ Obsolete] Milton.

Spinthariscope Spin·thar"i·scope noun [ Greek spinqari`s spark + -scope .] A small instrument containing a minute particle of a radium compound mounted in front of a fluorescent screen and viewed with magnifying lenses. The tiny flashes produced by the continual bombardment of the screen by the α rays are thus rendered visible. -- Spin*thar`i*scop"ic adjective

Spinule Spin"ule noun [ Latin spinula , dim. of spina a spine: confer French spinule .] A minute spine. Dana.

Spinulescent Spin`u·les"cent adjective (Botany) Having small spines; somewhat thorny.

Spinulose, Spinulous Spin"u·lose`, Spin"u·lous adjective [ Confer French spinuleux .] Covered with small spines.

Spiny Spin"y adjective [ From Spine .] 1. Full of spines; thorny; as, a spiny tree. 2. Like a spine in shape; slender. " Spiny grasshoppers sit chirping." Chapman. 3. Fig.: Abounding with difficulties or annoyances.

The spiny deserts of scholastic philosophy.

Bp. Warburton. Spiny lobster . (Zoology) Same as Rock lobster , under Rock . See also Lobster .

Spiny Spin"y noun See Spinny .

Spiodea Spi·o"de·a noun plural [ New Latin , from Spio the typical genus.] (Zoology) An extensive division of marine Annelida, including those that are without oral tentacles or cirri, and have the gills, when present, mostly arranged along the sides of the body. They generally live in burrows or tubes.

Spirable Spi"ra·ble adjective [ Latin spirabilis .] Capable of being breathed; respirable. [ Obsolete] Nash.

Spiracle Spir"a·cle noun [ Latin spiraculum , from spirare to breathe: confer French spiracule . See Spirit .] 1. (Anat.) The nostril, or one of the nostrils, of whales, porpoises, and allied animals. 2. (Zoology) (a) One of the external openings communicating with the air tubes or tracheæ of insects, myriapods, and arachnids. They are variable in number, and are usually situated on the sides of the thorax and abdomen, a pair to a segment. These openings are usually elliptical, and capable of being closed. See Illust. under Coleoptera . (a) A tubular orifice communicating with the gill cavity of certain ganoid and all elasmobranch fishes. It is the modified first gill cleft. 3. Any small aperture or vent for air or other fluid.

Spiracular Spi·rac"u·lar adjective Of or pertaining to a spiracle.

Spiral Spi"ral adjective [ Confer French spiral . See Spire a winding line.] 1. Winding or circling round a center or pole and gradually receding from it; as, the spiral curve of a watch spring. 2. Winding round a cylinder or imaginary axis, and at the same time rising or advancing forward; winding like the thread of a screw; helical. 3. (Geom.) Of or pertaining to a spiral; like a spiral. Spiral gear , or Spiral wheel (Machinery) , a gear resembling in general a spur gear, but having its teeth cut at an angle with its axis, or so that they form small portions of screws or spirals. -- Spiral gearing , a kind of gearing sometimes used in light machinery, in which spiral gears, instead of bevel gears, are used to transmit motion between shafts that are not parallel. -- Spiral operculum , an operculum whih has spiral lines of growth. -- Spiral shell , any shell in which the whorls form a spiral or helix. -- Spiral spring . See the Note under Spring , noun , 4.

Spiral Spi"ral noun [ Confer French spirale . See Spiral , adjective ] 1. (Geom.) A plane curve, not reëntrant, described by a point, called the generatrix , moving along a straight line according to a mathematical law, while the line is revolving about a fixed point called the pole . Confer Helix . 2. Anything which has a spiral form, as a spiral shell. Equiangular spiral , a plane curve which cuts all its generatrices at the same angle. Same as Logarithmic spiral , under Logarithmic . -- Spiral of Archimedes , a spiral the law of which is that the generatrix moves uniformly along the revolving line, which also moves uniformly.

Spirality Spi·ral"i·ty noun The quality or states of being spiral.

Spirally Spi"ral·ly adverb In a spiral form, manner, or direction.

Spiralozooid Spi·ra`lo·zo"oid noun [ Spiral + zooid . So called because they often have a spiral form when contracted.] (Zoology) One of the special defensive zooids of certain hydroids. They have the form of long, slender tentacles, and bear lasso cells.

Spirant Spi"rant noun [ Latin spirans , -antis , present participle of spirare to breathe. See Spirit .] (Phon.) A term used differently by different authorities; -- by some as equivalent to fricative , - - that is, as including all the continuous consonants, except the nasals m , n , ng ; with the further exception, by others, of the liquids r , l , and the semivowels w , y ; by others limited to f , v , th surd and sonant, and the sound of German ch , -- thus excluding the sibilants, as well as the nasals, liquids, and semivowels. See Guide to Pronunciation , §§ 197-208.

Spiranthy Spi·ran"thy noun [ Greek ......... a coil + ......... flower.] (Botany) The occasional twisted growth of the parts of a flower.

Spiration Spi·ra"tion noun [ Latin spiratio , from spirare to breathe.] The act of breathing. [ Obsolete] Barrow.

Spire Spire intransitive verb [ Latin spirare to breathe. See Spirit .] To breathe. [ Obsolete] Shenstone.