Drill

A drill comprising:

• a rake face;
• a negative land continuous to the rake face;
• a flank face continuous to the negative land;
• and
• an outer circumferential surface continuous to the rake face, the negative land, and the flank face, wherein
• a ridgeline between the rake face and the negative land constitutes a lower cutting edge,
• a ridgeline between the flank face and the negative land constitutes an upper cutting edge,
• when viewed in a direction along a rotation axis of the drill, the negative land includes
• a first region in which a space between the upper cutting edge and the lower cutting edge becomes wider toward the outer circumferential surface, and
• a second region which is continuous to the first region and in which the space becomes wider toward the rotation axis,
• in a cross section perpendicular to the rotation axis, the rake face includes a return face continuous to the outer circumferential surface, the return face being recessed opposite to a rotation direction of the drill,
• when a first boundary represents a boundary between the outer circumferential surface and the first region and a second boundary represents a boundary between the first region and the second region, a length of the first boundary is larger than a length of the second boundary in a direction parallel to the rotation axis, and
• the second boundary is continuous to the return face.