viceroy
‘person ruling as representative of a sovereign’
Lexical development traced from the Tamil root:
E. viceroye, vizeroye, vizroy < F. vice-roy < O.F. vice- ‘deputy’ + roi ‘king’ < Lat. regem < rex ‘king’ < regere ‘to keep straight, guide, lead, rule’ < roy < reg- < Tamil aracaṉ