Gripe: "Restoration." Yea right.

To me restoration means it was a car that was in a not driveable condition. Restored to a driveable condition.

A car that is "restored" should need absolutely nothing to pass a safety, be insured and registered and driven daily.

That said. There is "levels" of restored in my mind.

Complete original/factory original: Everything is original. Everything. From the paint to the radio knobs. From the upholstery to the carpet. Technically not a "restored" vehicle because nothing has been restored (or it wouldn't be original) but had repairs or work to make it daily driveable (carb rebuilt, new gaskets, etc) when it wasn't before.
Numbers matching: Exactly as it sounds. We all know what this is.
Period correct: A vehicle that has a factory correct engine block, but not numbers matching. Or factory correct seats that have been reupholstered. Etc. You get the idea. The car LOOKS as though it was just bought off showroom floor. Even if it's not all original.
Restored: A car that wasn't driveable previously. But has now been made driveable. Can pass all safety stuff. Be daily driven. BUT still retains the original cars "character". So no crazy mods like fender flares. Or huge 20 inch wheels. Still has full interior. When you look at it, you know what it is.
Resto-mod: Cars that have been restored, but also modified so they lost some of the "original character" they had. See - Chip Foose cars.

There's obviously a lot more to it. But in my mind, any one of these cars could be called "restored". Anything that wasn't driveable before but has been made driveable now is "restored" in my mind. Maybe not numbers matching. But restored none the less.