surrogate
‘a substitute’
Lexical development traced from the Tamil root:
E.surragat, suragat < Lat. surrogatus < surrogare/subrogare ‘put in another’s place, substitute’ < sub ‘in the place of, under’ + rogare ‘to ask, propose’ < ruhg < reg- < Tamil aracaṉ
Other meaning: Psychology: a figure of authority who takes the place of father or mother in a person’s unconscious or emotional life.