Definition of sociate in English:

Late 15th century (in an earlier sense). Originally from classical Latin sociāt-, past participial stem of sociāre to attach as a partner or associate, to unite, to make common cause, to possess jointly, share, to combine, bring together from socius companion. In later use partly aphetic from associate. Compare Middle French socier to ally (someone to oneself), French socier to have friendly relations (with someone). Compare earlier socie.