Glam metal or Hair metal is just a publicity name more than anything, the elements of the average glam "metal" group are much more akin to rock than metal.
Therefore "Glam Rock" would be the correct terminology according to me.
I never considered Def Leppard's albums up to Pyromania to be hair metal or glam rock whichever term you want to use... it was a little above that... also WASP, Quiet Riot, Twisted Sister etc.. were not hair/glam neither IMO