A compressor aerofoil for a turbine engine, the compressor aerofoil comprising: a root portion spaced apart from a tip portion by a main body portion; the main body portion defined by: a suction surface wall having a suction surface, a pressure surface wall having a pressure surface, whereby the suction surface wall and the pressure surface wall meet at a leading edge and a trailing edge, the tip portion comprising, in a cross-sectional view,: a shoulder provided on the pressure surface wall between the leading edge and the trailing edge; a tip wall which extends from the aerofoil leading edge to the aerofoil trailing edge; a transition region of the pressure surface wall which tapers from the shoulder in a direction towards the tip wall, the tip wall comprising: a squealer defined by a first tip wall region which extends from the trailing edge to a winglet defined by a second tip wall region which increases in width relative to the first tip wall region to a tip wall widest point (A-A), and then reduces in width towards the leading edge, characterised in that along the length of the winglet, the winglet is narrower than a distance wbA between the pressure surface and the suction surface in the corresponding region of winglet, wherein the widest point (A-A) of the winglet has width w3A of at least 0.8 wbA but no more than 0.95 wbA, wherein the tip wall defines a tip surface which extends from the aerofoil leading edge to the aerofoil trailing edge; and at the widest point (A-A) of the winglet: the transition region of the pressure surface wall extends from the shoulder in a direction towards the suction surface, and at an inflexion point the transition region curves to extend in a direction away from the suction surface toward the tip surface. a root portion spaced apart from a tip portion by a main body portion; the main body portion defined by: a suction surface wall having a suction surface, a pressure surface wall having a pressure surface, whereby the suction surface wall and the pressure surface wall meet at a leading edge and a trailing edge, a suction surface wall having a suction surface, a pressure surface wall having a pressure surface, whereby the suction surface wall and the pressure surface wall meet at a leading edge and a trailing edge, the tip portion comprising, in a cross-sectional view,: a shoulder provided on the pressure surface wall between the leading edge and the trailing edge; a tip wall which extends from the aerofoil leading edge to the aerofoil trailing edge; a transition region of the pressure surface wall which tapers from the shoulder in a direction towards the tip wall, the tip wall comprising: a squealer defined by a first tip wall region which extends from the trailing edge to a winglet defined by a second tip wall region which increases in width relative to the first tip wall region to a tip wall widest point (A-A), and then reduces in width towards the leading edge, a shoulder provided on the pressure surface wall between the leading edge and the trailing edge; a tip wall which extends from the aerofoil leading edge to the aerofoil trailing edge; a transition region of the pressure surface wall which tapers from the shoulder in a direction towards the tip wall, the tip wall comprising: a squealer defined by a first tip wall region which extends from the trailing edge to a winglet defined by a second tip wall region which increases in width relative to the first tip wall region to a tip wall widest point (A-A), and then reduces in width towards the leading edge, a squealer defined by a first tip wall region which extends from the trailing edge to a winglet defined by a second tip wall region which increases in width relative to the first tip wall region to a tip wall widest point (A-A), and then reduces in width towards the leading edge, characterised in that along the length of the winglet, the winglet is narrower than a distance wbA between the pressure surface and the suction surface in the corresponding region of winglet, wherein the widest point (A-A) of the winglet has width w3A of at least 0.8 wbA but no more than 0.95 wbA, wherein the tip wall defines a tip surface which extends from the aerofoil leading edge to the aerofoil trailing edge; and at the widest point (A-A) of the winglet: the transition region of the pressure surface wall extends from the shoulder in a direction towards the suction surface, and at an inflexion point the transition region curves to extend in a direction away from the suction surface toward the tip surface. the transition region of the pressure surface wall extends from the shoulder in a direction towards the suction surface, and at an inflexion point the transition region curves to extend in a direction away from the suction surface toward the tip surface.