Part 343

Ple`o*mor"phism (?), n. [Gr. &?; more + &?; form.] 1. (Crystallog.) The property of crystallizing under two or more distinct fundamental forms, including dimorphism and trimorphism.

2. (Biol.) The theory that the various genera of bacteria are phases or variations of growth of a number of Protean species, each of which may exhibit, according to undetermined conditions, all or some of the forms characteristic of the different genera and species.

Ple`o*mor"phous (?), a. Having the property of pleomorphism.

Ple"o*nasm, (&?;), n. [L. pleonasmus, Gr. &?;, fr. &?; to be more than enough, to abound, fr.&?;, neut. of &?;, more, compar. of &?; much. See Full, a., and cf. Poly-, Plus.] (Rhet.) Redundancy of language in speaking or writing; the use of more words than are necessary to express the idea; as, I saw it with my own eyes.

Ple"o*nast (?), n. One who is addicted to pleonasm. [R.] C. Reade.

Ple"o*naste, n. [Gr.&?; abundant, rich; cf. F. plÈonaste.] (Min.) A black variety of spinel.

{ Ple`o*nas"tic (?), Ple`o*nas"tic*al (?), } a. [Cf. F. plÈonastique.] Of or pertaining to pleonasm; of the nature of pleonasm; redundant.

Ple`o*nas"tic*al*ly, adv. In a pleonastic manner.

Ple"o*pod (?), n.; pl. E. Pleopods (#), L. Pleopoda (#). [Gr. &?; to swim + -pod.] (Zoˆl.) One of the abdominal legs of a crustacean. See Illust. under Crustacea.

Ple"rome (?), n. [Gr. &?; that which fills up, fr. &?; to fill.] (Bot.) The central column of parenchyma in a growing stem or root.

Ple*roph"o*ry (?), n. [Gr. &?;; &?; full + &?; to bear.] Fullness; full persuasion. "A plerophory of assurance." Bp. Hall.

Ples"ance (?), n. Pleasance. [Obs.] Chaucer.

Plesh (?), n. A pool; a plash. [Obs.] Spenser.

Ple`si*mor"phism (?), n. [Gr. &?; near + &?; form.] (Crystallog.) The property possessed by some substances of crystallizing in closely similar forms while unlike in chemical composition.

Ple`si*o*mor"phous (?), a. Nearly alike in form.

Ple"si*o*saur (?), n. (Paleon.) One of the Plesiosauria.

||Ple`si*o*sau"ri*a (?), n. pl. [NL. See Plesiosaurus.] (Paleon.) An ||extinct order of Mesozoic marine reptiles including the genera ||Plesiosaurus, and allied forms; -- called also Sauropterygia.

Ple`si*o*sau"ri*an (?), n. (Paleon.) A plesiosaur.

||Ple`si*o*sau"rus (?), n.; pl. Plesiosauri (#). [NL., fr. Gr &?; near ||+ &?; a lizard.] (Paleon.) A genus of large extinct marine reptiles, ||having a very long neck, a small head, and paddles for swimming. It ||lived in the Mesozoic age.

Ples*sim"e*ter (?), n. See Pleximeter.

Plete (?), v. t. & i. To plead. [Obs.] P. Plowman.

Pleth"o*ra (?), n. [NL., fr. Gr. &?;, fr. &?; to be or become full. Cf. Pleonasm.] 1. Overfullness; especially, excessive fullness of the blood vessels; repletion; that state of the blood vessels or of the system when the blood exceeds a healthy standard in quantity; hyperÊmia; -- opposed to anÊmia.

2. State of being overfull; excess; superabundance.

He labors under a plethora of wit and imagination.

Jeffrey.

Pleth`o*ret"ic (?), a. Plethoric. [Obs.] Johnson.

Ple*thor"ic (?), a. [Gr. &?;; cf. F. plÈthorique.] Haeving a full habit of body; characterized by plethora or excess of blood; as, a plethoric constitution; -- used also metaphorically. "Plethoric phrases." Sydney Smith. "Plethoric fullness of thought." De Quincey.

Ple*thor"ic*al (?), a. Plethoric. [R.] -- Ple*thor"ic*al*ly, adv. Burke.