Knock knock. Thump thump. Pew Pew! Oh, Baby! Pushy. Mercy.
It's pretty clear that at some point the devs gave up on thinking of decent names for the unique weapons and just started naming them the first thing to pop into their heads (unless John Stamos is famous for his grenade machinegunning skills, in which case it's a pretty good name).
So throw out some suggestions to rename some of the worst uniques. I'm pretty certain anybody here can come up with a better name for a fire axe than "knock-knock".