Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
sŭburbānĭtas, ātis, f. [suburbanus], nearness to the city of Rome: suburbanitas hujusce provinciae (Siciliae), * Cic. Verr. 2, 2, 3, § 7; Symm. Ep. 2, 22; Sid. Ep. 7, 2 med.