An airfoil (101; 102; 201; 301; 401; 801a; 801b) of a gas turbine engine comprising: an airfoil body (209; 309; 409) having a platform (210; 310; 810a; 810b), at least one internal flow passage (218, 318), a first surface (214; 314) and a second surface (216; 316), the first surface defining a wall of the at least one internal flow passage, and the platform extending from the second surface; and a bleed port (219; 319; 419; 619; 719) fluidly connecting the at least one internal flow passage to the second surface, the bleed port comprising: a bleed orifice (220; 320; 420; 620; 820a; 820b) extending from the second surface toward the internal flow passage; and a bleed port cavity (226; 326; 426; 526; 626; 826) extending from the first surface toward the second surface, the bleed port cavity and the bleed orifice fluidly connected, the bleed port cavity defined by: a bleed port cavity wall (228a; 228b; 328a; 328b; 428a; 428b; 528); and a base wall (230; 330) surrounding the bleed orifice, wherein the bleed port cavity wall extends from the first surface to the base wall; wherein the bleed port is located through a portion of the airfoil body below the platform; and the bleed port cavity has a wider end formed within the first surface and a narrower end connected to the base wall and the bleed orifice, the bleed port cavity being configured to increase an upstream pressure feeding the bleed orifice and to direct air to turn before the air enters the bleed orifice; the airfoil being characterised in that the base wall runs parallel to the first and second surfaces. an airfoil body (209; 309; 409) having a platform (210; 310; 810a; 810b), at least one internal flow passage (218, 318), a first surface (214; 314) and a second surface (216; 316), the first surface defining a wall of the at least one internal flow passage, and the platform extending from the second surface; and a bleed port (219; 319; 419; 619; 719) fluidly connecting the at least one internal flow passage to the second surface, the bleed port comprising: a bleed orifice (220; 320; 420; 620; 820a; 820b) extending from the second surface toward the internal flow passage; and a bleed port cavity (226; 326; 426; 526; 626; 826) extending from the first surface toward the second surface, the bleed port cavity and the bleed orifice fluidly connected, the bleed port cavity defined by: a bleed port cavity wall (228a; 228b; 328a; 328b; 428a; 428b; 528); and a base wall (230; 330) surrounding the bleed orifice, wherein the bleed port cavity wall extends from the first surface to the base wall; a bleed orifice (220; 320; 420; 620; 820a; 820b) extending from the second surface toward the internal flow passage; and a bleed port cavity (226; 326; 426; 526; 626; 826) extending from the first surface toward the second surface, the bleed port cavity and the bleed orifice fluidly connected, the bleed port cavity defined by: a bleed port cavity wall (228a; 228b; 328a; 328b; 428a; 428b; 528); and a base wall (230; 330) surrounding the bleed orifice, wherein the bleed port cavity wall extends from the first surface to the base wall; a bleed port cavity wall (228a; 228b; 328a; 328b; 428a; 428b; 528); and a base wall (230; 330) surrounding the bleed orifice, wherein the bleed port cavity wall extends from the first surface to the base wall; wherein the bleed port is located through a portion of the airfoil body below the platform; and the bleed port cavity has a wider end formed within the first surface and a narrower end connected to the base wall and the bleed orifice, the bleed port cavity being configured to increase an upstream pressure feeding the bleed orifice and to direct air to turn before the air enters the bleed orifice; the airfoil being characterised in that the base wall runs parallel to the first and second surfaces.