The Antoninos

'Alienist' and 'alien' are related - both are ultimately derived from the Latin word 'alius', meaning 'other'. In French, the adjective 'aliéné' (insane) gave rise to the noun 'alieniste', referring to a doctor who treats the insane.

'Alienist' is much rarer than 'psychiatrist' these days, but at one time it was the preferred term.