It seems like an almost pretentious thing, the ''cool kids'' in the know will scoff at anyone who calls it a fixie... and those who have never gotten into the ss/fg culture are predisposed to the term fixie so thats what they use. I've heard ''fixie'' come from really dumb college aged kids, to bicycle shop owners. Seems to be a if you know, you know kinda deal. Just my .02...
I personally call it a fixed gear, BUT do I care at all what someone else calls it? **** no! Call it a turd covered in more turd, don't care