arm·pit 
/ˈɑɚmˌpɪt/ noun
plural arm·pits /ˈɑɚmˌpɪt/ noun [count] 1 : the hollow area on a person's body beneath the place where the arm and the shoulder meet —called also underarm; — see picture at human 2 US, informal : the worst area in a place
▪ a city described as the armpit of America
▪ a city described as the armpit of America
