/ Dictionary / Index A Arthus' reaction: Meaning and Definition of Find definitions for: Ar•thus'' reac'tion Pronunciation: (är-t'siz), [key] — Immunol. Immunol. a severe, local immune reaction to the injection of an antigen in a sensitized host. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Arthurian artichoke Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language