/ Dictionary / Index R regulator pin: Meaning and Definition of Find definitions for: reg'ulator pin" Pronunciation: [key] either of two pins on the regulators of certain timepieces, one on each side of the hairspring, that can be moved to adjust the rate of the timepiece. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. regulator regulatory gene Related Content Daily Word Quiz: censure Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language