'arbitratorship' originates from English, specifically formed from the word 'arbitrator' + the suffix '-ship', where 'arbitrator' ultimately comes from Latin 'arbiter' meaning 'judge' and the suffix '-ship' (from Old English 'scipe' / Proto‑Germanic *skapiz) meant 'state, condition, or office'.

'arbitratorship' developed in modern English by adding the noun-forming suffix '-ship' to 'arbitrator' (which passed into English via Old French/Anglo-French from Latin 'arbiter'), producing a word meaning the office or condition of an arbitrator.

Initially and historically it has denoted 'the office or role of an arbitrator'; this core meaning has largely been retained into modern usage.