'cytolysin-neutralizing' originates as a modern English compound combining 'cytolysin' and 'neutralize'. 'cytolysin' is formed from New Latin/Greek roots 'cyto-' (from Greek kytos, "cell") + 'lysis' (Greek lysis, "loosening, breaking") with the -in suffix for substances; 'neutralize' comes from French neutraliser and English 'neutral' + the verb-forming suffix -ize.

'cytolysin' was coined in biomedical New Latin in the 19th/20th century from Greek roots 'kytos' and 'lysis' and the material suffix '-in'; 'neutralize' entered English via French neutraliser (from neutral) and the productive suffix -ize; the compound 'cytolysin-neutralizing' is a modern, descriptive English formation combining the technical noun and the verb (present participle).

Initially the constituents meant 'cell' (kytos) and 'loosening/breaking' (lysis) for cytolytic activity, and 'to make neutral' for neutralize; combined, the compound has the straightforward modern sense 'rendering a cell-lysing toxin inactive' with little semantic shift from component meanings.