/ Dictionary / Index P prime cost: Meaning and Definition of Find definitions for: prime' cost' Pronunciation: [key] that part of the cost of a commodity deriving from the labor and materials directly utilized in its manufacture. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. prime prime field Related Content Daily Word Quiz: knead Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language