also: こすれあう
godan verb (-u), intransitive verb
rub against each other; chafe; quarrel
Physical rubbing or friction between objects, or metaphorically for people clashing or quarreling. The quarrel sense is a figurative extension.
電車の中で隣の人と肩が擦れ合った。
My shoulder rubbed against the person next to me on the train.
The two often quarrel because of their differing opinions.