A woman who is very ugly - like godzilla, except they have nice looking breasts
"Did you see that woman walking past? - she was a real Boobzilla"
A woman who uses her breasts to gain or hold attention because of being otherwise deficient.
Good thing she's got boobzillas, because she's so butt-ugly she'd have to tie a steak around her neck for the dogs to play with her.
A girl who is packing very big breasts, but lacks hotness or is on the heavy side.
"Oh my gawd its boobzilla"
In the world of Adult, performer Desiree Deluca is known as Boobzilla--she's a hot, red-headed MILF with 34F natural boobs. She's definitely earned the title and has been recently been dubbed a legend by Hot Movies for Her based on her amazing mammaries.
Damn, look at that girl, Desiree Deluca. She's got amazing tits--and they're HUGE. Her boobs dwarf everything in their presence. They're like Godzilla, but they're boobs (AKA Boobzilla).