Nozzle assembly for a fluid injector, having - a nozzle body with a central axis, wherein the nozzle body has a nozzle body recess, at least one injection opening, and an external wall facing away from the nozzle body recess, - a nozzle clamping nut by means of which the nozzle body can be coupled to an injector body, wherein the nozzle clamping nut has an internal wall facing toward the external wall of the nozzle body, - wherein the nozzle body and the nozzle clamping nut are designed such that, under the action to which the nozzle body recess is subjected by a normal operating pressure of a fluid to be metered, the external wall of the nozzle body bears at least partially against the internal wall of the nozzle clamping nut in a radial direction, - wherein an overlap region is provided in which the nozzle body overlaps the nozzle clamping nut in a radial direction, wherein the overlap region extends in an axial direction from a first end, facing away from the injection opening, to a second end, facing toward the injection opening, - wherein, under the action to which the nozzle body recess is subjected by the normal operating pressure of the fluid to be metered, the external wall of the nozzle body in the first subregion bears at least partially against the internal wall of the nozzle clamping nut in the radial direction, characterized in that a first subregion of the overlap region extends in the axial direction from the first end to a contact point at which the nozzle body bears in the axial direction against the nozzle clamping nut, and in that at least one section of the external wall of the nozzle body is of convex form in the first subregion. - a nozzle body with a central axis, wherein the nozzle body has a nozzle body recess, at least one injection opening, and an external wall facing away from the nozzle body recess, - a nozzle clamping nut by means of which the nozzle body can be coupled to an injector body, wherein the nozzle clamping nut has an internal wall facing toward the external wall of the nozzle body, - wherein the nozzle body and the nozzle clamping nut are designed such that, under the action to which the nozzle body recess is subjected by a normal operating pressure of a fluid to be metered, the external wall of the nozzle body bears at least partially against the internal wall of the nozzle clamping nut in a radial direction, - wherein an overlap region is provided in which the nozzle body overlaps the nozzle clamping nut in a radial direction, wherein the overlap region extends in an axial direction from a first end, facing away from the injection opening, to a second end, facing toward the injection opening, - wherein, under the action to which the nozzle body recess is subjected by the normal operating pressure of the fluid to be metered, the external wall of the nozzle body in the first subregion bears at least partially against the internal wall of the nozzle clamping nut in the radial direction, characterized in that a first subregion of the overlap region extends in the axial direction from the first end to a contact point at which the nozzle body bears in the axial direction against the nozzle clamping nut, and in that at least one section of the external wall of the nozzle body is of convex form in the first subregion.