Underhooks

From FightWiki

An underhook is a grappling term for a clinch hold that is used to control the opponent. It is performed from any direction by putting an arm under the opponents arm, and holding the opponents midsection or upper body. Having an underhook with one arm is called a single underhook, while having underhooks with both arms is known as double underhooks. The typical response to an underhook is to try to break it, or to establish an overhook. This is because underhooks use the opponents arms to apply leverage and thus control the opponent across the cage or secure a takedown.