An opsonin acting upon bacteria, as distinguished from a haemopsonin which affects red blood corpuscles. ... (05 Mar 2000) ... 
(bak-tēr″e-op´so-nin) an opsonin that acts on bacteria.
Type: Term Pronunciation: bak-tēr′ē-op′sō-nin Definitions: 1. An opsonin that may be an antibody and activated complement complex bound to bacteria rendering them susceptible to phagocytic cells.