noun
: a boring bit having one or more spurs which scribe the periphery of the hole in advance of the cutting lips to guide the bit in the proper direction — compare twist bit
noun
: a boring bit having one or more spurs which scribe the periphery of the hole in advance of the cutting lips to guide the bit in the proper direction — compare twist bit
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012