/ Dictionary / Index M mentally: Meaning and Definition of Find definitions for: men•tal•ly Pronunciation: (men'tl-ē), [key] — adv. in or with the mind or intellect; intellectually. with regard to the mind. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: mentally (Thesaurus) mentality mental reservation Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language