Sealing member, a turbine, and a gas turbine

Vanes, the stationary blade body extending radially of the axis, and an outer shroud provided at an outer end in the radial direction of the vane body, and the outer shroud is provided on the inner end portion in the radial direction of the vane body having an inner shroud (8b) forming the main flow path of combustion gases between a retainer (8d) that protrudes from the inner surface of the radially inner shroud (8b) inward in the radial direction. Mutual retainer (8d) in the stationary blade adjacent in the circumferential direction are adjacent via the third gap in the circumferential direction, the third gap, to the end, downstream of the direction along the axis of the combustion gas other end side is closed by a seal member located (20b).