a substance in blood serum acting on bacteria and foreign cells to make them more liable to destruction by phagocytes
Origin of opsoninobsolete opson(ium), relish ( from Classical Latin from Classical Greek ops?nion, food, provisions from ops?nein, to buy food from opson, meat or any food eaten with bread from o-, together with + an unverified form ps?n, food, bread, akin to ps?mos, mouthful) + -in
A substance, such as an antibody or complement protein, that binds to a bacterium or other pathogen and causes it to become more susceptible to the action of phagocytes.
Origin of opsoninLatin opsōnāre to buy provisions ( from Greek opsōnein ) ( from opson condiment, delicacy ; see epi in Indo-European roots.) -in