a popular dare made by bad 'friends' where everyone must place their tongue on the location on his body chosen by the original shouter, it must be shouted until complete
everyone is bored someone shouts 'Lick Ryan' so everyone in the room must lick him
To give it your all. A saying coming from how Eskimos kill wolves by having them lick frozen seal blood off of knives, therefore the wolves gave literally everything to lick a knife.
That actor left everything on the stage. They really did lick the knife!