/ Dictionary / Index C comma fault: Meaning and Definition of Find definitions for: com'ma fault" Pronunciation: [key] — Gram. Gram. the use of a comma, rather than a semicolon, colon, or period, to separate related main clauses in the absence of a coordinating conjunction: often considered to be incorrect or undesirable, esp. in formal writing. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Commack Commager Related Content Daily Word Quiz: diaphanous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language