/ Dictionary / Index C C clef: Meaning and Definition of Find definitions for: C clef Pronunciation: [key] — Music. Music. a clef that, according to its position, locates middle C on the first, third, or fourth line of the staff. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. C-clamp C.Cls. Related Content Daily Word Quiz: arboreal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language