/ Dictionary / Index M main clause: Meaning and Definition of Find definitions for: main' clause' Pronunciation: [key] a clause that can stand alone as a sentence, containing a subject and a predicate with a finite verb, as I was there in the sentence I was there when he arrived. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. main chance main course Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language