late Old English cachepol "tax-gatherer," from Old North French cachepol (Old French chacepol), from Medieval Latin cacepollus "a tax gatherer," perhaps literally "chase-chicken." For first element see chase (v.), for second see pullet. The explanation would be that, in lieu of taxes they would confiscate poultry. Later in English more specifically as "a sheriff's officer whose duty was to make arrests for debt" (late 14c.). Compare Old French chacipolerie "tax paid to a nobleman by his subjects allowing them and their families to shelter in his castle in war-time." The connection of poll (n.) "head" with taxes is too late to be involved in this word.