The act of being an uggo.
Yo, Steph is uggin. Hard. You shouldn't hit it.
by The Chil October 01, 2006
an ugly third nipple or mole, usually on the torso. an ugly version of Chandler's nubbin or third nipple from the television show Friends.
my boyfriend has an uggin on his back.
by littlebethb August 03, 2005