A drill which includes a cylindrical main body and a shank contiguous to
each other, and which is to be rotated about an axis of the cylindrical
main body in a predetermined rotating direction, for enlarging a hole
previously formed in a workpiece through a die-casting process. The
cylindrical main body has flutes which are formed in the cylindrical
mainbody and extend from an axially distal end portion of the cylindrical
main body toward the shank, so as to provide cutting edges in the axially
distal end portion of the cylindrical main body. The cutting edges
cooperate with each other to define a point angle which is larger than
170.degree. and is smaller than 180.degree.. Each of the cutting edges is
substantially straight or is curved to be convexed as seen in the
direction perpendicular to the axis.