'bay' (sense: to bark) originates from Old French, specifically the word 'baier' or 'baer', where the form meant 'to bark or bay'.

'bay' changed from Old French 'baier' into Middle English forms such as 'baien'/'bayen' and eventually became the modern English verb 'bay'.

Initially, it referred primarily to the sound made by hounds ('to bark' or 'to bay'); over time it also developed figurative senses such as 'to drive into a corner' and 'to shout/demand loudly'.