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mūnĭcĭpĭum, ii, n. [municeps], a town, particularly in Italy, which possessed the right of Roman citizenship (together with, in most cases, the right of voting), but was governed by its own laws; a free town (cf. municeps; syn.: civitas, oppidum): Sex. Roscius, pecuniā sui municipii facile primus, Cic. Rosc. Am. 6, 15: nullum erat Italiae municipium, id. Sest. 14, 32: e municipio antiquissimo Tusculano, id. Planc. 8, 19.
Sometimes for colonia: L. Castronius longe princeps municipii Lucensis, Cic. Fam. 13, 13 init.