short, pointed hand-to-hand weapon

A dagger is a knife which is used to stab people. It has a double-edged blade, so it cannot be used for normal cutting like a knife.

Neolithic dagger
Modern Winchester Riot Dagger and sheath

Daggers are small, so they can often be hidden under the attacker's clothing and then suddenly produced.

They were also used in the Middle Ages for the infantry armies to defend or attack their opponents.

Some people like Julius Caesar were assassinated with a dagger.