/ Dictionary / Index C crank letter: Meaning and Definition of Find definitions for: crank' let"ter Pronunciation: [key] a hostile or fanatical letter, often sent anonymously. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. crankle crankpin Related Content Daily Word Quiz: abstain Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language