/ Dictionary / Index P polybasic: Meaning and Definition of Find definitions for: pol•y•ba•sic Pronunciation: (pol"ē-bā'sik), [key] — adj. Chem. (of an acid) having two or more atoms of replaceable hydrogen. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. polyatomic polybasite Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language