'purpose-made' is a compound of 'purpose' + 'made'. 'purpose' originates from Old French (Anglo-French) specifically the word 'porpos' / 'purpose', where Latin 'propositum' (from 'pro-' meaning 'forth' and 'ponere' meaning 'to put') is the ultimate source. 'made' is the past participle of 'make', which originates from Old English 'macian' (to make).

'purpose' passed into Middle English from Old French/Anglo-French and 'made' developed as the past form of Old English 'macian'; the compound 'purpose-made' arose in Modern English by combining the noun 'purpose' with the past participle 'made' to denote something made for that purpose.

Initially the elements separately meant 'an intention/aim' (purpose) and 'constructed/produced' (made); combined, they have long meant 'constructed for a specific purpose', a meaning that has remained stable into modern usage.