A wall of a component of a gas turbine engine subjected to a flow of high temperature gas, the wall comprising: first and second wall surfaces (102, 104); an inlet (110; 210) located at the first wall surface; an outlet located at the second wall surface; a metering section (112; 212) commencing at the inlet (110; 210) and extending downstream from the inlet (110; 210); and a diffusing section (114; 214) extending from the metering section and terminating at the outlet, the diffusing section comprising: a first lobe (124; 224) diverging longitudinally and laterally from the metering section and having a first downstream end adjacent the outlet and spaced from the inlet by a first distance; a second lobe (126; 226) diverging longitudinally from the metering section and having a second downstream end adjacent the outlet and spaced from the inlet (110; 210) by a second distance different from the first distance; and a first transition region positioned between the first and second lobes, the first transition region comprising a third downstream end adjacent the outlet, characterized by the diffusing section (114; 214) further comprising: a second transition region positioned between the first transition region and the second lobe, the second transition region comprising a fourth downstream end adjacent the outlet. first and second wall surfaces (102, 104); an inlet (110; 210) located at the first wall surface; an outlet located at the second wall surface; a metering section (112; 212) commencing at the inlet (110; 210) and extending downstream from the inlet (110; 210); and a diffusing section (114; 214) extending from the metering section and terminating at the outlet, the diffusing section comprising: a first lobe (124; 224) diverging longitudinally and laterally from the metering section and having a first downstream end adjacent the outlet and spaced from the inlet by a first distance; a second lobe (126; 226) diverging longitudinally from the metering section and having a second downstream end adjacent the outlet and spaced from the inlet (110; 210) by a second distance different from the first distance; and a first transition region positioned between the first and second lobes, the first transition region comprising a third downstream end adjacent the outlet, a first lobe (124; 224) diverging longitudinally and laterally from the metering section and having a first downstream end adjacent the outlet and spaced from the inlet by a first distance; a second lobe (126; 226) diverging longitudinally from the metering section and having a second downstream end adjacent the outlet and spaced from the inlet (110; 210) by a second distance different from the first distance; and a first transition region positioned between the first and second lobes, the first transition region comprising a third downstream end adjacent the outlet, characterized by the diffusing section (114; 214) further comprising: a second transition region positioned between the first transition region and the second lobe, the second transition region comprising a fourth downstream end adjacent the outlet. a second transition region positioned between the first transition region and the second lobe, the second transition region comprising a fourth downstream end adjacent the outlet.