/ Dictionary / Index I insecticide: Meaning and Definition of Find definitions for: in•sec•ti•cide Pronunciation: (in-sek'tu-sīd"), [key] — n. a substance or preparation used for killing insects. the act of killing insects. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: insecticide (Thesaurus) insectary insectifuge Related Content Daily Word Quiz: pundit Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language