No no, you call it a "Fixie", especially if it is actually a single speed... right? Ahem.

I do agree that the terms "single speed" and "fixed gear" technically should have nothing to do with the type of bike. My Electra Rally Sport is a single speed.... and even though it has racing stripes, it is not even remotely a "road bike".

Terminology can get a bit weird, though. I see people referring to geared bikes (often IGH) as "fixies", because they look like "fixies".

Basically, it's a bit unpractical to try to identify the type of bike solely by the type of drive train...It's a bit like identifying your bike by the material it's made of, yes it's relevant information, but it isn't enough information...