twin city
noun
1- either of two neighbouring cities lying close together两座彼此临近的城市之一。
1.1
the Twin Cities
N. Amer. Minneapolis and St Paul in Minnesota〈北美〉双子城（指明尼苏达州的明尼阿波利斯和圣保罗两市）。
1.2
- a city which has been twinned with another姐妹城。