The act of forcing back alcohol using the facial cheek muscles, with the end goal of getting trashed as quickly as possible. Can also be used as a descrete way to ask others if they want to participate.
âCome on over man, bring the IPAâs, Iâve been cheekinâ since 5:00!â
âSo are we still cheekinâ later? Donât let First Sergeant find out.â