/ Dictionary / Index C chain rule: Meaning and Definition of Find definitions for: chain' rule" Pronunciation: [key] — Math. Math. the theorem that defines the method for taking the derivative of a composite function. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. chain reactor chain saw Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language