A simple test of strength that sometimes occurs when two alpha males shake eachother's hands for the first time. The process includes squeezing as hard as you can until one person gives up.

(noun) A successful type of theft which results in an acceptable, impressive and rewarding payday for the protagonist.

When someone is holding an item (usually a drink) and you slap their hand(s) in an attempt to make the person drop the item. This is accompanied by yelling "Grip check!".