Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
gnāve, gnāvĭtas, gnāvĭter, gnāvus, v. under nav-.
nāvĭtas (gnāv-), ātis, f. [navus], promptness, assiduity, zeal: istam operam tuam, navitatem, animum in rem publicam, etc., Cic. Fam. 10, 25, 1: gnavitas studiosa, Arn. 1, p. 3.