/ Dictionary / Index H hemolysin: Meaning and Definition of Find definitions for: he•mol•y•sin Pronunciation: (hi-mol'i-sin, hē"mu-lī'-, hem"u-), [key] — n. Immunol. a substance, as an antibody, that in cooperation with complement causes dissolution of red blood cells. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: hemolysin (Thesaurus) hemolymph hemolysis Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language