under the hood or bonnet, so frunk is becoming a more popular term again

Ah yeah see, without learning the word frunk I would have said bonnet storage or just bonnet, then I read your other comment saying that the bonnet is the metal flap, so that's another TIL!

Tailgate in Australia means to drive up someone's arse/not keep the safe distance between you and the driver in front, I'm guessing deriving from that they're on your tailgate. Interesting stuff, thanks.