FUEL INJECTOR NOZZLE, FUEL INJECTOR, INTERNAL COMBUSTION ENGINE, AND VEHICLE

A fuel injector nozzle () is disclosed. The nozzle () comprises a nozzle tip (′) comprising an inner surface () and an outer surface (). The nozzle () further comprises a number of fuel injection holes () each forming an inlet opening () at the inner surface () and an outlet opening () at the outer surface (). At least one fuel injection hole () has a geometrical centre line (c) being curved along at least a first portion (p) of the at least one fuel injection hole (). The radius of curvature (r) of the geometrical centre line (c) increases as seen in a direction (d′) from the inlet opening () towards the outlet opening (). The radius of curvature (r1) increases continuously along the full first portion (p) of the at least one fuel injection hole () as seen in the direction (d′) from the inlet opening () towards the outlet opening (). A fuel injector (), an internal combustion engine (), and a vehicle () are also disclosed.