Knuckle duster and Weapon system

Knuckle duster noun - A small metal weapon; worn over the knuckles on the back of the hand.

Weapon system and knuckle duster are semantically related. In some cases you can use "Weapon system" instead a noun phrase "Knuckle duster".

Weapon system noun - Any instrument or instrumentality used in fighting or hunting.

Knuckle duster and weapon system are semantically related. Sometimes you can replace phrase "Knuckle duster" with "Weapon system", this phrases are similar.