/ Dictionary / Index C circular pitch: Meaning and Definition of Find definitions for: cir'cular pitch' Pronunciation: [key] — Mach. Mach. See under (def. 49a). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. circular mil circular polarization Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language