Lewis Short
mētrŏpŏlis (noun F) = μητρόπολις:
* A city from which other cities have been colonized, a mother-city; also, the chief city, metropolis of a province (post-class.).
* Lit., Cod. Just. 11, 21; Cod. Th. 13, 3, 11.
* Trop.: metropolis et arx mentis,Hier. adv. Jovin. 2, 8.
Charlton T. Lewis, Charles Short, A Latin Dictionary