Greek.Sounds booh-los. Originally means bird (mpoulos<-poulos<-pouli=bird) but indicates the dick. Commonly used to express disappointment, frustration, hopelessness or as a swear to express the dominance over another person, football team etc.
hopelessness: Malaka an xasoume to treno, 8a paroume to boulo
Malaka if we miss the train we will take the boulo (in this context "we are fucked")
dominance and/or dare: Ere boulo pou 8a paroune simera oi pasokoi!
Oh boulo that PASOK-funs will take today!
Ti boulos itan autos!
What a boulos was that!