"bright flame, fire," Old English blæse "a torch, firebrand; bright glowing flame," from Proto-Germanic *blas- "shining, white" (source also of Old Saxon blas "white, whitish," Middle High German blas "bald," originally "white, shining," Old High German blas-ros "horse with a white spot," Middle Dutch and Dutch bles, German Blesse "white spot," blass "pale, whitish"), from PIE root *bhel- (1) "to shine, flash, burn."