/ Dictionary / Index D dimethoate: Meaning and Definition of Find definitions for: di•meth•o•ate Pronunciation: (dī-meth'ō-āt"), [key] — n. Chem. a highly toxic crystalline compound, CHNOPS, used as an insecticide. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. dimeter dimethoxymethane Related Content Daily Word Quiz: labyrinth Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language