Sorry if I had started a dumb topic. That was not my intention. I guess the only prerequisite for a lager is lager yeast. I suppose temp doesn't matter.
Sorry, man, didn't mean to offend, directly, anyway. I just thought it seemed like a fairly obvious answer. As a brewer who brews mostly lagers, I guess I'm a bit biased? It would seem Mark has a more scientific answer, even though I don't agree with the cold storage argument. Maybe he didn't read my post about Zwicklbier, zoiglbier, kellerbier, etc. Those beers aren't lagered for long periods of time, although kellerbier is longer than the other two, but still...it's typically still cloudy and young. You think Germans call those lagers? You bet they do. And by that same logic, altbier is typically lagered for long periods, but they don't call those lagers, same for Kolsch.
Any beer can be fined and dropped bright or filtered, making it look like a lager with very little time in cold storage. Does this make it not a lager since it isn't being stored cold for long periods? Still think that's not good enough of an argument.