| pyrenoid | <plant biology> Small body found within some chloroplasts, that may contain protein. In green algae may be involved in starch synthesis. (18 Nov 1997) |
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| pyrethrin | <chemistry> A substance resembling, and isomeric with, ordinary camphor, and extracted from the essential oil of feverfew. Synonym: Pyrethrum camphor. Origin: NL. Pyrethrum, generic name of feverfew, Gr. Feverfew. Source: Websters Dictionary (01 Mar 1998) |
| pyrethrine | <chemistry> An alkaloid extracted from the root of the pellitory of Spain (Anacyclus pyrethrum). Source: Websters Dictionary (01 Mar 1998) |
| pyrethrins | <chemical> The active insecticidal constituent of pyrethrum flowers. Pyrethrin I is the pyretholone ester of chrysanthemummonocarboxylic acid and pyrethrin II is the pyretholone ester of chrysanthemumdicarboxylic acid monomethyl ester. Pharmacological action: insecticide, botanical. (12 Dec 1998) |
| pyrethroids | Synthetic pyrethrin derivatives that are used as insecticides; as a class these agents are less toxic to mammals than are other effective insecticides. (05 Mar 2000) |
| pyrethrolone | 2-Methyl-4-oxo-3-(2,4-pentanedienyl)-2-cyclopentenol, a constituent of the pyrethrins. (05 Mar 2000) |
| pyrethrum | <plant biology> A natural insecticide that is extracted from chrysanthemums. It is atoxic, nonvolatile hydrocarbon related to kerosene. (09 Oct 1997) |
| pyretic | <medicine> Of or pertaining to fever; febrile. Origin: Gr. Burning heat, fever, from fire: cf. F. Pyretique. Source: Websters Dictionary (01 Mar 1998) |
| pyreto- | Fever. See: pyr-, pyro-. Origin: G. Pyretos, fever, fr. Pyr, fire (05 Mar 2000) |
| pyretogen | Rarely used term for pyrogen. Origin: pyreto-+ G. -gen, producing (05 Mar 2000) |
| pyretogenesis | Rarely used term for the origin and mode of production of fever. Origin: pyreto-+ G. Genesis, origin (05 Mar 2000) |
| pyretogenetic | <physiology> Fever inducing. Origin: Gr. Gennan = to produce (18 Nov 1997) |
| pyretogenous | 1. Causing fever. Synonym: pyrogenic. (05 Mar 2000) |
| pyretology | <study> A discourse or treatise on fevers; the doctrine of fevers. Origin: Gr. Fever: cf. F. Pyretologie. Source: Websters Dictionary (01 Mar 1998) |
| pyretotherapy | 1. Obsolete synonym for pyrotherapy. 2. Treatment of fever. Synonym: artificial fever, induced fever. Origin: pyreto-+ G. Therapeia, treatment (05 Mar 2000) |