'arbitratrix' originates from Latin, specifically the word 'arbitrātrīx', where 'arbiter' meant 'judge' or 'one who considers' and the suffix '-trīx' marked a feminine agent.

'arbitratrix' came from Classical/Medieval Latin 'arbitrātrīx' (female form of 'arbiter'/'arbitrator') and was borrowed into English usage (particularly in legal contexts), eventually existing in modern English as 'arbitratrix' though it is now rare.

Initially it meant 'female judge or arbiter', and over time it has retained the sense 'female arbitrator' though modern usage favors the gender-neutral 'arbitrator'.