'overseas-backed' is a compound formed from 'overseas' and 'backed'. 'overseas' originates from Old English elements 'ofer' and 'sǣ', where 'ofer' meant 'over' and 'sǣ' meant 'sea'. 'backed' is the past participle of the verb 'back', which originates from Old English 'bæc' meaning 'back' or 'rear'.

'overseas' changed from Old English phrases like 'ofer sǣ' and Middle English variants into the modern word 'overseas'; 'back' comes from Old English 'bæc' and via Middle English forms became the verb 'back' and its past participle 'backed'. The compound adjective 'overseas-backed' developed in modern English usage (especially in finance and politics) to describe entities supported from abroad.

Initially, 'overseas' meant 'across the sea' and 'backed' meant 'supported from behind'; together they evolved to mean 'supported or funded from abroad' in contemporary usage.