A liner for a prosthesis, wherein the liner is made of a liner material and comprises a proximal opening for accommodating an amputation stump, a distal end, a longitudinal direction, which extends from the proximal opening to the distal end, and an auxetic material The auxetic material is a two-dimensional-auxetic material, which is arranged in such a way that an extension of the liner in the longitudinal direction leads to an expansion of a diameter of the liner.