It is a multi-purpose word used in an awkward situation, to disagree, to saygross, to signify a time to laugh, or just to shout out whenever you need it!
Coined by Dr.Perry Cox from the medical comedy show Scrubs, it is now used as an overall exclamatory remark towards anything deemed angering, sexy, cool etc.
(pretty woman kisses her malefriend without warning; causes a long winded "oooooooh" from the audience)
A verbal insult that implies how one is so unaesthetically appealing to the the eye that even the canine species would find him/her unrecognizable to a point where it would feel compelled to bark as a warning for said individual to maintain their distance.
"Man my woof factor is through the roof today. I haven't showered in over a week and I no longer fit in my sweat pants"