Well "verifiability" means the ability to show that it is true. Something verifiable is demonstrably true. WP verifiability means something different. 'being cited as true by a trusted source' seems close but you can't blame users for Wikipedia's misuse of a word. Of course that just shifts the focus to what is a trusted source ... presumably the answer is one that is true ...

I can prove it too ... http://en.wiktionary.org/wiki/verify [lol!].