godan verb (-u), intransitive verb
touch each other; come into contact
Describes two or more things physically touching or brushing against each other. Often used for body parts, objects, or abstract contact.
電車の中で隣の人と肩が振り合った。
My shoulder touched the person next to me on the train.
木の枝が風で振り
The tree branches are touching each other in the wind and making noise.