euphemism for Hell, 1818, plural of blaze (n.1), in reference to the flames.
Entries linking to blazes
blaze n.1
"bright flame, fire," Middle English blase, from 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."