/ Dictionary / Index D direction cosine: Meaning and Definition of Find definitions for: direc'tion co"sine Pronunciation: [key] — Math. Math. the cosine of the angle made by a given vector and a coordinate axis. Cf. direction angle. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. direction angle direction finder Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language