'hemolysis-preventing' is a modern compound formed from 'hemolysis' and 'preventing'. 'hemolysis' comes ultimately from Greek elements 'haima' (blood) + 'lysis' (loosening, breaking) via New Latin, and 'preventing' derives from Latin 'praevenire' (to come before, to hinder) via Old French 'prevenir'.

'hemolysis' entered English in medical New Latin in the 19th century from Greek 'haima' + 'lysis'; 'prevent' passed from Latin 'praevenire' → Old French 'prevenir' → Middle English 'prevenen'. The adjective 'hemolysis-preventing' is a recent English formation combining the medical noun with an -ing participle to form a descriptive adjective.

The component elements originally referred to 'breaking of blood (cells)' and 'coming before / hindering'; combined in modern usage they denote 'acting to stop the rupture or destruction of red blood cells', a sense used in medical and technical contexts.