percussion cap

1. 1.

   a detonator that explodes when struck

   Broaderdetonator

   Partsmercury fulminate

Questions about percussion cap

What does percussion cap mean?

percussion cap means "a detonator that explodes when struck".

Is percussion cap a common word?

percussion cap is banded "Rare" — specialist or archaic — most readers will not have met it. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.