What is "blasting cap"

n. a small tube filled with detonating substances; used to detonate high explosives

A blasting cap is a small sensitive primary explosive device generally used to detonate a larger, more powerful and less sensitive secondary explosive such as TNT, dynamite, or plastic explosive.

Blasting caps come in a variety of types, including non-electric caps, electric caps, and fuse caps. They are used in commercial mining, excavation, and demolition. Electric types are set off by a short burst of current conducted from a blasting machine by a long wire to the cap to ensure safety. Traditional fuse caps have a fuse which is ignited by a flame source, such as a match or a lighter.