Pyroacid noun [ Pyro- + acid .] (Chemistry) An acid obtained by sybjecting another acid to the action of heat. Confer Pyro- .

Pyroantimonate noun (Chemistry) A salt of pyroantimonic acid.

Pyroantimonic adjective [ Pyro- + antimonic .] (Chemistry) Pertaining to, or designating, an acid of antimony analogous to pyrophosphoric acid.

Pyroarsenate noun (Chemistry) A salt of pyroarsenic acid.

Pyroarsenic adjective [ Pyro- + arsenic .] (Chemistry) Pertaining to or designating, an acid of arsenic analogous to pyrophosphoric acid.

Pyroborate noun (Chemistry) A salt of pyroboric acid.

Pyroboric adjective [ Pyro- + boric .] (Chemistry) Pertaining to derived from, or designating, an acid, H ₂ B ₄ O ₇ (called also tetraboric acid), which is the acid ingredient of ordinary borax, and is obtained by heating boric acid.

Pyrocatechin noun [ Pyro- + catechu .] (Chemistry) A white crystalline substance, C ₆ H ₄ (OH) ₂ , of the phenol series, found in various plants; -- so called because first obtained by distillation of gum catechu . Called also catechol , oxyphenol . etc.

Pyrochlore noun [ Pyro- + Greek ... pale green.] (Min.) A niobate of calcium, cerium, and other bases, occurring usually in octahedrons of a yellowish or brownish color and resinous luster; -- so called from its becoming grass-green on being subjected to heat under the blowpipe.

Pyrocitric adjective [ Pyro- + citric : confer French pyrocitrique .] (Chemistry) Pertaining to, or designating, any one of three acids obtained by the distillation of citric acid, and called respectively citraconic , itaconic , and mesaconic acid.

Pyrocoll (pĭr"o*kŏl) noun [ Puro- + Greek ko`lla glue.] (Chemistry) A yellow crystalline substance allied to pyrrol, obtained by the distillation of gelatin.

Pyroelectric adjective [ Pyro- + electric .] (Physics) Pertaining to, or dependent on, pyroelectricity; receiving electric polarity when heated.

Pyroelectric noun (Physics) A substance which becomes electrically polar when heated, exhibiting opposite charges of statical electricity at two separate parts, especially the two extremities.

Pyroelectricity noun (Physics) Electricity developed by means of heat; the science which treats of electricity thus developed.

Pyrogallate noun (Chemistry) A salt of pyrogallic acid; an ether of pyrogallol.

Pyrogallic adjective [ Pyro- + gallic .] (Chemistry) Pertaining to, derived from, or designating, an acid called pyrogallol . See Pyrogallol .

Pyrogallol noun [ Pyrogallic + -ol .] (Chemistry) A phenol metameric with phloroglucin, obtained by the distillation of gallic acid as a poisonous white crystalline substance having acid properties, and hence called also pyrogallic acid . It is a strong reducer, and is used as a developer in photography and in the production of certain dyes.

Pyrogen noun [ See Pyrogenous .]
1. Electricity. [ R.]

2. (Physiol. Chem.) A poison separable from decomposed meat infusions, and supposed to be formed from albuminous matter through the agency of bacteria.

Pyrogenic adjective [ Pyro- + -gen + -ic .] (Physiol.) Producing heat; -- said of substances, as septic poisons, which elevate the temperature of the body and cause fever.

Pyrogenous adjective [ Greek ... fire + genous : confer French purogène , Greek ....] Produced by fire; igneous. Mantell. .

Pyrognostic adjective [ Pyro- + Greek ... to know.] (Min.) Of or pertaining to characters developed by the use of heat; pertaining to the characters of minerals when examined before the blowpipe; as, the pyrognostic characters of galena.

Pyrognostics noun plural (Min.) The characters of a mineral observed by the use of the blowpipe, as the degree of fusibility, flame coloration, etc.

Pyrograph noun A production of pyrography.

Pyrography noun [ Pyro- + -graphy .] A process of printing, ornamenting, or carving, by burning with heated instruments.

Pyrogravure noun [ Pyro- + French gravure engraving.] Pyrography; also, a design or picture made by pyrography.

Pyrolator noun [ See Pyrolatry .] A fire worshiper. [ R.] Southey.

Pyrolatry noun [ Pyro- + Greek ... worship: confer French pyrolâtrie .] The worship of fire. Young.

Pyroligneous, Pyrolignic adjective [ Pyro -+ Latin lignum wood: confer French pyroligneux .] (Old Chem.) Pertaining to, or designating, the acid liquid obtained in the distillation of wood, consisting essentially of impure acetic acid.

Pyrolignite noun A crude acetate produced by treating pyroligneous acid with a metal or basic compound; as, pyrolignite of iron (iron liquor).

Pyrolignous adjective Same as Pyroligneous .

Pyrolithic adjective [ Pyro- + lithic .] (Old Chem.) Same as Pyrouric , or Cyanuric .

Pyrologist noun One who is versed in, or makes a study of, pyrology.

Pyrology noun [ Pyro- + - logy : confer French pyrologie .] That branch of physical science which treats of the properties, phenomena, or effects of heat; also, a treatise on heat.

Pyrolusite noun [ Pyro- + Greek ... to loose, or ... a loosing.] (Min.) Manganese dioxide, a mineral of an iron-black or dark steel-gray color and metallic luster, usually soft. Pyrolusite parts with its oxygen at a red heat, and is extensively used in discharging the brown and green tints of glass (whence its name).

Pyromagnetic adjective [ Pyro- + magnetic .] (Physics) Acting by the agency of heat and magnetism; as, a pyromagnetic machine for producing electric currents.

Pyromalate noun (Chemistry) A salt of pyromalic acid. [ Obsolete]

Pyromalic adjective [ Pyro- + malic .] (Old Chem.) Pertaining to, or designating, an acid now called maleic acid .

Pyromancy noun [ Greek ...; ... fire + ... divination: confer French pyromancie .] Divination by means of fire.

Pyromania noun [ Pyro- + mania .] An insane disposition to incendiarism.

Pyromantic adjective Of or pertaining to pyromancy.

Pyromantic noun [ Confer Greek ....] One who pretends to divine by fire. Sir T. Herbert.

Pyrometer noun [ Pyro- + -meter : confer French pyromètre .]
1. (Physics) An instrument used for measuring the expansion of solid bodies by heat.

2. (Physics) An instrument for measuring degrees of heat above those indicated by the mercurial thermometer.

» It is usually constructed so as to register the change which the heat to be measured produces in the length of some expansible substance, as a metallic rod, or in the intensity of a thermo-electric current.

Pyrometric, Pyrometrical adjective [ Confer French pyrométrique .] (Physics) Pertaining to, or obtained by, the pyrometer; as, pyrometrical instruments; pyrometrical measurements.

Pyrometry noun The art of measuring degrees of heat, or the expansion of bodies by heat.

Pyromorphite noun [ German pyromorphit , from Greek ... fire + ... form.] (Min.) Native lead phosphate with lead chloride, occurring in bright green and brown hexagonal crystals and also massive; -- so called because a fused globule crystallizes in cooling.

Pyromorphous adjective [ Pyro- + -morphous .] (Min.) Having the property of crystallizing by the agency of fire.

Pyromucate noun (Chemistry) A salt of pyromucic acid.

Pyromucic adjective [ Pyro- + mucic .] (Chemistry) Pertaining to, derived from, or designating, an acid obtained as a white crystalline substance by the distillation of mucic acid, or by the oxidation of furfurol.

Pyrone noun [ German pyron , an abbr. of pyrokoman .] (Org. Chem.) An unsaturated cyclic compound, C ₅ H ₄ O ₂ , of which two varieties are known, α and γ. γ-pyrone is the parent substance of several natural yellow dyestuffs.

Pyronomics noun [ Pyro- + Greek ... law.] The science of heat.