/ Dictionary / Index J Jack Frost: Meaning and Definition of Find definitions for: Jack' Frost' Pronunciation: [key] frost or freezing cold personified. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. jackfish jackfruit Related Content Daily Word Quiz: fabricate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language