Dot

An adjective referring to something or somebody from Dorchester (see Dot. Ave., OFD and rat).

It is NOT a synonym for "Dorchester," however. As OFDer Jim Sullivan notes:

People from Southie were the ones who called Dorchester "Dot". The only acceptable use of "Dot" was when speaking about the street "Dot Ave" or the public space "Dot Park". Everyone knew you were an outsider if you referred to the actual town by saying "Dot".