Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
in-sĕnesco, nui, 3, v. inch. n., to grow old in or at a thing; constr. with dat. (poet. and post-Aug. prose): insenuit Libris et curis, Hor. Ep. 2, 2, 82: malis, Ov. P. 1, 4, 48: singulis actionum partibus, Quint. 10, 3, 11: iisdem negotiis, Tac. A. 4, 6.