/ Dictionary / Index J jackstone: Meaning and Definition of Find definitions for: jack•stone Pronunciation: ( jak'stōn"), [key] — n. jack (def. 5a, b). jack (def. 5c). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. jackstay jackstraw Related Content Daily Word Quiz: blanch Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language