Tony raised both of his eyebrows and blinked at Seven for a few seconds. He wondered far along in her storyline she'd been when she ended up here, how long she'd been a part of a human crew. But then, in the far future, language probably didn't contain idioms like 'cool' anyway. So he tried not to laugh, and instead waved a hand to the side like he was dashing a thought away.
"Cool. It's an idiom for... a couple of things, actually. In this case it just means 'good' or 'excellent', or 'something that is awesome when it happens'. So when I say 'that was not cool' I mean that it definitely was not good or excellent or an awesome thing that happened. It was the opposite of fun."