/ Dictionary / Index H halloo: Meaning and Definition of Find definitions for: hal•loo Pronunciation: (hu-l'), [key] — pl. v.i., v.t., -loos, -looed, -loo•ing. hallo. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: halloo (Thesaurus) Hall of Famer hallow Related Content Daily Word Quiz: immense Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language