pentacyclic (pent as i klik)

[ πέντε, five: see five.] 1. The number five, in the abstract; a set of five things considered together: as, the Pythagorean pentad: correlated with monad, dyad, triad, tetrad, etc. Specifically-2. A period of five consecutive years. The means of the last two pentads , 1866-70 and 1871–75, were almost exactly the same as the grand mean. J. D. Whitney, Climatic Changes, p. 337. 3. In chem . , an element one atom of which will combine with five univalent atoms or radicals; a pentavalent element. pentadactyl, pentadactyle (pen-ta-dak'til), a. and n. [Cf. L. pentadactyl us, a starfish; II. n. A pentadactyl or quin que digitate ani mal; any member of the Pentadactyl a. Pentadactyl a, Pentadactyl i (pen-ta-dak'tilä, -li), n. pl. [NL., neut. or masc. pl. of pent a dactylus:: see pentadactyl.] A supercla division of gnat hos to mous vertebrates supposed to have been derived from pentadactylous ances cies have lost one or more of the digits, and some even a pair or all of the limbs, such as the snakes, cetaceans, etc. -Pentadactyl a branch i at a, a synonym of Amphibia: a name given by E. R. Lankester to the amphibians as a "grade" of gnat hos to mous craniate vertebrates inter me diate between the Heterodactyl a branch i at a (true fishes and dipnoans) and the Pentadactyl a lipo branchia (reptiles, birds, and mammals). [Little used.] - Pentadactyl a lipo branchia, a name given by E. R. Lankester to the highest "grade" of vertebrates, being a series which includes reptiles, birds, and mammals, as collectively dis 4379