'sanction' originates from Latin, specifically the word 'sanctio', where the root 'sancire' meant 'to make sacred' or 'to decree'.

'sanction' came into English via Old French 'sanction' (from Latin 'sanctio') and Middle English maintained the form 'sanction', eventually developing both senses of 'approval/authorization' and 'penalty'.

Initially, it meant 'a decree or making something sacred/authorized'; over time it came to mean both 'official approval' and (by extension) 'a penalty imposed to enforce compliance', the latter sense becoming prominent in political contexts.