'suffixation' originates from Latin elements via English: it is built from 'suffix' + the noun-forming suffix '-ation'. The English noun 'suffix' comes from Latin 'suffixus' (past participle of 'suffigere'), where 'sub-' (later 'suf-') meant 'under' and 'figere' (from 'figere'/'figo') meant 'to fix' or 'to fasten'.

'suffix' entered English from Latin (often via Old French/Medieval Latin usage) as a term for an element 'fastened underneath' or 'attached after' a stem, and Modern English formed 'suffixation' by adding the productive Latin-derived suffix '-ation' (from Latin '-ationem') to denote the action or process.

Initially related to the literal idea of 'fixing/attaching (under/after)', the term evolved to the specific linguistic sense of 'the act/process of adding a suffix to a word', which is its modern meaning.