pyrochemˈical adjective

Relating to, producing, or produced by, chemical changes at high temperatures

pyroclasˈtic adjective (Gr klastos broken; geology)

(of rocks) formed of fragments thrown out by volcanic action

pyroclasˈtics plural noun

Ash and other debris ejected by a volcano (also singular noun pyˈroclast)

pyro-elecˈtric adjective (physics)

1. Becoming positively and negatively electrified at opposite poles on heating or cooling
2. Of pyro-electricity

pyro-electricˈity noun

1. The property of being pyro-electric
2. The study of the phenomena shown by pyro-electric crystals

pyrogallol /-galˈol/ noun

A phenol obtained by heating gallic acid, used in photographic developing (also called pyrogallˈic acid)

pyˈrogen /-jen/ noun (see -gen; medicine)

A substance causing heat or fever

pyrogenic /pī-rō-jenˈik/, pyrogenetic /-jin-etˈik/ or pyrogenous /-rojˈə-nəs/ adjective

Produced by, or producing, heat or fever

pyrognostic /pī-rog-nosˈtik/ adjective

(see -gnostic under gnosis) relating to the testing of minerals by flame

pyrognosˈtics plural noun

The properties of a mineral revealed by such testing

pyrography /pī-rogˈrə-fi/ noun

(see -graphy) poker work

pyrogravure /-grə-vūrˈ/ noun

(Fr gravure engraving) pyrography

pyrokinesis /-kī-nēˈsis or -ki-nēˈsis/ noun

(Gr kīnēsis movement) the ability to start fires by thought alone

pyrolater /pī-rolˈə-tər/ noun

A fire-worshipper

pyrolˈatry noun

(see -latry) fire-worship

pyroligneous /-ligˈni-əs/ adjective (L ligneus, from lignum wood; chem)

Obtained by distillation of wood (pyroligneous acid wood vinegar, a mixture of acetic acid, methyl alcohol, etc; pyroligneous alcohol wood spirit, methyl alcohol)

pyrolusite /-lūˈsīt or -looˈsīt/ noun (Gr lousis washing, from its use in decolorizing molten glass; geology)

Naturally-occurring manganese dioxide

pyˈrolyse or (N American) pyˈrolyze transitive verb

To decompose by pyrolysis

pyrolysis /pi-rolˈi-sis/ noun

(see lysis) decomposition of a substance by heat

pyrolytic /-litˈik/ adjective

pyromancy /-man-si/ noun

(see -mancy) divination by fire

pyromāˈnia noun

An obsessive urge to set light to things

pyromāˈniac noun and adjective

pyromaniacal /-mə-nīˈə-kl/ adjective

pyromanˈtic adjective

Relating to pyromancy

pyromeride /pī-romˈər-īd/ noun (Gr meros part, as if meaning only partly fusible; geology)

A nodular rhyolite

pyrometallurgy /-metˈəl-ûr-ji or -met-alˈər-ji/ noun

The art and science of treating metals with high temperatures

pyrometer /pī-romˈi-tər/ noun

(see -meter) an instrument for measuring high temperatures

pyrometric /pī-rō-metˈrik/ or pyrometˈrical adjective

(pyrometric cones same as Seger cones)

pyromˈetry noun

pyromorphite /-mörˈfīt/ noun

(Gr morphē form) a minor ore (chloride and phosphate) of lead, so called because the globule formed by heating a small quantity of ore crystallizes on cooling

pyrophobia /-fōˈbi-ə/ noun

(see phobia) an irrational fear of fire

pyrophōˈbic noun and adjective

pyˈrophone /-fōn/ noun

(Gr phōnē sound) an organ producing interference-tones by pairs of flames in tubes, invented by Eugène Kastner (1852–82)

pyrophoric /-rō-forˈik/ and pyrophˈorous adjective

pyrophorus /pī-rofˈə-rəs/ noun (Gr pyrophoros fire-carrier)

1. A substance that takes fire on exposure to air (chem)
2. (with cap) a genus of tropical American fireflies, the elaterid beetles

pyrophosphate noun see above

pyrophosphoric adjective see above

pyrophoˈtograph noun

A burnt-in photograph, eg on glass or porcelain

pyrophotographˈic adjective

pyrophotogˈraphy noun

pyrophyllite /-filˈīt/ noun

(Gr phyllon leaf) a clay mineral that separates into layers on heating with a blowpipe

pyˈroscope /-skōp/ noun

(see -scope) an instrument for measuring the intensity of radiant heat

pyrosis /pī-rōˈsis/ noun

(Gr pyrōsis) water brash, heartburn

Pyrosoma /-sōˈmə/ noun

(Gr sōma body) a genus of compound tunicates, with brilliant phosphorescence

pyˈrosome noun

pyˈrostat /-stat/ noun

A type of thermostat for use at high temperatures

pyrostatˈic adjective

pyrosulphate noun see above

pyrosulphuric, pyrotartaric, etc adjective see above

pyrotechˈnic or pyrotechˈnical adjective

pyrotechˈnically adverb

pyrotechnician /-nishˈən/ noun

A person who makes fireworks or puts on firework displays

pyrotechnics /-tekˈniks/ singular noun

1. (Gr technikos skilled, from technē art) the art of making fireworks
2. (also plural noun) a display (or the displaying) of fireworks
3. (also plural noun) showy display in talk, music, etc
4. (also plural noun) a display of temper

pyrotechˈnist noun

1. A pyrotechnician
2. A person given to pyrotechnics

pyˈrotechny noun

Pyrotechnics

pyroxene /pī-roksˈēn/ noun

(Gr xenos stranger, because the 18c French mineralogist Haüy thought that pyroxene crystals in lava had been caught up accidentally) a general name for an important group of minerals distinguished from amphiboles by a cleavage angle of about 87º, metasilicates of calcium, magnesium, aluminium and other metals, usu green or black, very common in igneous rocks such as augite, diopside, enstatite, etc

pyroxenic /-senˈik/ adjective

pyroxˈenite /-ən-īt or -ēnˈīt/ noun

A rock compound essentially of pyroxene

pyroxyle /-rokˈsil/ noun same as pyroxylin below

pyroxylic /-silˈik/ adjective (obsolete)

Pyroligneous

pyroxylin or pyroxyline /-rokˈsi-lin/ noun

(Gr xylon wood) any of the nitrocelluloses