'temporarily-hired' is a modern English compound formed from the adverb 'temporarily' and the past-participial adjective 'hired'. 'Temporarily' ultimately comes from Latin 'temporarius' (via Old French/Latin-derived Middle English), where 'tempus' meant 'time'; 'hire' comes from Old English 'hyran' meaning 'to employ for pay.'

'temporarily' developed from Latin 'temporarius' → Old French/Latin-influenced Middle English 'temporary' → English adverb 'temporarily'; 'hire' came from Old English 'hyran' and gave Modern English 'hire' and past form 'hired'; these elements combined in English to form phrases such as 'temporarily hired' and occasionally the hyphenated adjective 'temporarily-hired'.

Initially, 'temporarius' meant 'relating to time', and 'hire' meant 'to obtain services for pay'; over time the combined phrase came to specifically mean 'employed for a limited period' in modern usage.