[Obsolete French
 aliéniste, psychiatrist : obsolete French
 aliéné, mentally ill (from past participle of
 aliéner, to estrange, make hostile, deprive of reason, from
 Old French, from
 Latin
 aliēnāre, to deprive of reason; see 
 ALIENATE) + French
 -iste, -ist (from
 Old French; see 
 -IST).]