mētrŏpŏlis

is, f.
I. a city from which other cities have been colonized, a mother-city; also, the chief city, metropolis of a province (post-class.).
I. Lit., Cod. Just. 11, 21; Cod. Th. 13, 3, 11.—
II. Trop.: metropolis et arx mentis, Hier. adv. Jovin. 2, 8.
Lewis & Short
A Latin Dictionary, 1879
An open-access project