/ Dictionary / Index T terribly: Meaning and Definition of Find definitions for: ter•ri•bly Pronunciation: (ter'u-blē), [key] — adv. in a terrible manner. extremely; very: It's terribly late. I'm terribly sorry. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: terribly (Thesaurus) terrible terricolous Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language