/ Dictionary / Index A atactic: Meaning and Definition of Find definitions for: a•tac•tic Pronunciation: (ā-tak'tik), [key] — adj. Chem. (of a polymer) not stereospecific; lacking tacticity. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: atactic (Thesaurus) atacamite ataghan Related Content Daily Word Quiz: portent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language