Sophisticated or impressive. See posh.
"Karin, your loft is so fancypants!"
1.Pants that are particularly fancy today.
2.Shoved on the end of anyone's name who happens to be particularly fancy.
N.B. Your fancyness can not exceed that of Lappo,Circus,Timothy and Bradley as they are all fancier than thou.
Hold your pinky up as high as you can and exclaim "Fancier than thou!"..as long as your pinky is the highest you are the fanciest...other than the aforementioned fancypantses.
Well, big fucking deal! (sarcastic)
Zach: I finally slept with Dan's mother!
John: Fung tao pai fancypants, bitch. That must have been a real conquest, heh heh...