What is "push dagger"

n. A short bladed dagger with a handle (often T-shaped) designed to be grasped in the hand with the blade protruding out from between the fingers.

A push dagger (alternately known as: push knife, gimlet knife, fist knife, Stoßdolch (German), push dirk, T-handled knife or punch dagger) is a short-bladed dagger with a "T" handle designed to be grasped in the hand so that the blade protrudes from the front of one's fist, typically between the index and middle finger. Over the centuries, the push dagger has gone up and down in popularity as a close-combat weapon for civilians and selected military forces.

The sale and possession of push daggers is prohibited in some countries, such as the United Kingdom and Canada. The laws of many nations and several U.S. states and cities prohibit or criminalize to some degree the purchase, possession, or sale of push daggers or knuckle knives.