A stator comprising: a cylindrical stator core; and an insulator installed on an axial-direction end surface of the stator core; the stator core having: a cylindrical part; a plurality of teeth protruding from an inner circumferential surface of the cylindrical part toward the radially inner side of the cylindrical part, and disposed along a circumferential direction of the cylindrical part; and a plurality of windings wound around each of the teeth; the winding having: a first end (e1 to e9) being a winding start part around the tooth; and a second end (c1 to c9) being a winding end part around the tooth; the insulator having a plurality of winding grooves (d1 to d9) configured to support the second end; each of the winding grooves supporting the second end of one of the plurality of windings; the winding groove having: a first space (81, 181, 281, 381) including an opening (83, 183, 283, 383); the opening being formed on an axial-direction end surface of the insulator that is not in contact with the stator core; the winding being wound around the tooth such that the second end exits from the radially inner side of the tooth; and the number of the winding grooves being the same as the number of the second ends, characterized in that the winding groove has a second space (82, 182, 282, 382) including a tip part (84, 184, 284, 384) configured to catch the second end, and communicating with the first space via a bent part (85, 185, 285, 385). a cylindrical stator core; and an insulator installed on an axial-direction end surface of the stator core; the stator core having: a cylindrical part; a plurality of teeth protruding from an inner circumferential surface of the cylindrical part toward the radially inner side of the cylindrical part, and disposed along a circumferential direction of the cylindrical part; and a plurality of windings wound around each of the teeth; a cylindrical part; a plurality of teeth protruding from an inner circumferential surface of the cylindrical part toward the radially inner side of the cylindrical part, and disposed along a circumferential direction of the cylindrical part; and a plurality of windings wound around each of the teeth; the winding having: a first end (e1 to e9) being a winding start part around the tooth; and a second end (c1 to c9) being a winding end part around the tooth; a first end (e1 to e9) being a winding start part around the tooth; and a second end (c1 to c9) being a winding end part around the tooth; the insulator having a plurality of winding grooves (d1 to d9) configured to support the second end; each of the winding grooves supporting the second end of one of the plurality of windings; the winding groove having: a first space (81, 181, 281, 381) including an opening (83, 183, 283, 383); the opening being formed on an axial-direction end surface of the insulator that is not in contact with the stator core; the winding being wound around the tooth such that the second end exits from the radially inner side of the tooth; and the number of the winding grooves being the same as the number of the second ends, characterized in that the winding groove has a second space (82, 182, 282, 382) including a tip part (84, 184, 284, 384) configured to catch the second end, and communicating with the first space via a bent part (85, 185, 285, 385).