That's hilarious! I know about cows licking, but I didn't know that.Some cattle have a tendency to lick people. They will search people out in the pen whenever they get a chance and it's very disgusting and annoying.
As a deterrent farmers would often tie the knot shown above around the cow's tongue and tie it off to a post. After 6 hours of not being to pull the tongue back into their mouth there were released and 90% of the time this broke them of the habit.
The name sprung from farmers saying they needed to "kill that cows lick". It was later shortened to Killick.
Alan
I've tied no cow tongues, but it's a great knot for skidding lodgepoles.