'arbitration' originates from Latin, specifically the word 'arbitrationem' (from 'arbiter'), where 'arbiter' meant 'judge' or 'independent witness' and the suffix '-ationem' indicated an action or process.

'arbitration' entered English via Old French (medieval) 'arbitracion' / Middle English 'arbitracioun', and eventually became the modern English word 'arbitration'.

Initially, it referred to the act or judgment of an individual 'arbiter'; over time it evolved to mean the formal process or system for resolving disputes outside the courts and the outcome of that process.