'non-auditability' is formed in English by the negative prefix 'non-' + 'auditability', where 'non-' means 'not' and 'auditability' is derived from 'audit' + the productive suffix '-ability' meaning 'capable of being'.

'audit' goes back to Latin 'audire' (to hear) and Latin 'auditus' (a hearing). It passed into Old French and then Middle English as 'audit' meaning an examination (originally a hearing of accounts), and '-ability' comes from Latin adjectival endings (via French/English '-able' and the noun-forming '-ability'). These elements combined in modern English to form 'auditability' and then the negated compound 'non-auditability'.

Initially 'audit' was connected to 'hearing' (from Latin 'audire'), and over time it became specialized to mean examination of accounts or verification; combined with '-ability' it came to mean 'capable of being audited'. The compound with 'non-' therefore evolved to mean 'not capable of being audited' in modern usage.