A lamp for use under water, comprising: an electrical lighting means, electrical connections for the power supply of the electrical lighting means, and a housing, wherein the housing is translucent at least in sections and defines a watertightly closable hollow space, wherein the electrical lighting means and the electrical connections are arranged within the hollow space, wherein the housing forms a mechanical shell surrounding the hollow space, the mechanical shell having a double curvature at each point of the shell; and a use of the lamp as a light bait when fishing.