Sentence:  The bookmaker's mean profit per dollar bet is called <WSD>vigorish</WSD> or “the vig.” In our example, 11 + 11 = $22 is bet, and the bookmaker wins $1 so the vig is 1/22 = 4.5%. 
Meaning of the word marked with <WSD> tags:  A charge taken on bets, as by a bookie or gambling establishment.