/ Dictionary / Index A allosaur: Meaning and Definition of Find definitions for: al•lo•saur Pronunciation: (al'u-sôr"), [key] — n. a carnivorous dinosaur of the genus Antrodemus (formerly Allosaurus), from the late Jurassic Period of North America, that was about 30 ft. (9 m) long. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: allosaur (Thesaurus) all-or-nothing allosteric Related Content Daily Word Quiz: digression Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language