/ Dictionary / Index M Mother's Day: Meaning and Definition of Find definitions for: Moth'er's Day" Pronunciation: [key] a day, usually the second Sunday in May, set aside in honor of mothers. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mother's boy mother's helper Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language