Taping knife
From Wikipedia, the free encyclopedia
A taping knife or joint knife is a drywall tool with a very large blade for spreading wide areas of joint compound over wallboard tape. It can also be used to patch wallboard and to smooth wall-coverings.
A right-angle joint knife allows one to apply joint compound to inside corners where walls meet. The handle is offset to allow clearance for fingers.
Source: "The Reader's Digest Book of Skills and Tools"