the phrase was coined during the world cup when the newspapers wanted to comment on the collective behaviour of the women the footballers took abroad with them - they called them footballers wives and girlfriends, hence footballers WAGs for short. What is really annoying me, as a stickler for correct language usage, is the newspapers now just calling them WAGs and not footballers WAGs, or saying someone is a WAG - as you noted in your original question this isn't possible!!