'arrestee' originates from English, specifically from the verb 'arrest' combined with the agent/patient-forming suffix '-ee'. The verb 'arrest' itself comes from Old French 'arester' (Middle French 'arrêter'), ultimately from Vulgar Latin *arrestare where ad- (to/toward) combined with Latin 'restare' (to remain/stop).

'arrest' changed from Old French 'arester' and Middle French 'arrêter' and entered Middle English as 'arresten' meaning 'to stop'. In English, the suffix '-ee' (from French -é via Anglo-Norman) was later added to form 'arrestee' meaning 'one who is arrested', producing the modern English 'arrestee' (plural 'arrestees').

Initially, 'arrest' mainly meant 'to stop' or 'to halt movement'; over time it shifted toward 'to detain or take into custody', and 'arrestee' came to mean 'a person who has been detained/arrested'.