She Unhinges Her Jaw Like a Python

Guy #1: Seriously, that girl has a mouth the size of a dinosaur.
Guy #2: What kind of dinosaur?
Guy #1: A big-mouthed dinosaur.

http://feeds.feedburner.com/~r/overheardinminneapolis/~3/288357279/rawr.html

Overheard by: he could have said any noun