I don't know, container is an abstract idea, and that's all. Can you run apps within a contained OS environment?

LXC is one way to do so, runc is another way to do so, docker is a third way to do so, all for Linux. Now if you took some other OS, there'd be different solutions, each with slightly different details and thus properties, but same idea.

I mean, do you ask people what SQL is? And get frustrated if they don't start talking about MySQL specific details like InnoDB and what not?

Don't know, I feel I can't agree with you, do devs feel there's less magic involved in VMs? Honestly, I have less idea what VMs are built on top of than I do for containers.