Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
dissēmĭnātĭo, ōnis, f. [dissemino], a scattering of seed, a sowing, disseminating (post-class.): evangelii, Tert. Fuga in Persec. 6.
In plur.: malevolorum, App. M. 11 fin.