I've seen it a lot with communication protocols for some reason, I guess it's just relatively clear it means "the non virtualized" even though it's clearly a misnomer. E.g. with VRRP a ton of people just say "the physical IP" when talking about the address that's not the VIP, even though the RFC refers to it as "the primary" IP. Arguably "primary IP" is more confusing as to which is being referred to, even though it's more technically accurate.

Of course, maybe there's a perfectly obvious word which can apply to all of those kinds of situations just as clearly without being a misnomer I've just never thought to mention in reply :D.