/ Dictionary / Index M moon letter: Meaning and Definition of Find definitions for: moon' let"ter Pronunciation: [key] any letter, as bā or mīm, representing a consonant that does not assimilate the l of a prefixed definite article. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. moonlet moonlight Related Content Daily Word Quiz: winsome Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language