What is "bangalore torpedo"

n. a metal pipe filled with explosive, used to detonate land mines or to clear a path through barbed wire

A Bangalore torpedo is an explosive charge placed within one or several connected tubes. It is used by combat engineers to clear obstacles that would otherwise require them to approach directly, possibly under fire. It is sometimes colloquially referred to as a "Bangalore mine", "banger" or simply "Bangalore".

Per United States Army Field Manual 5-250 section 1-14, page 1-12 "b. Use. The primary use of the torpedo is clearing paths through wire obstacles and heavy undergrowth. It will clear a 3- to 4-metre wide path through wire obstacles."