Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
dēnōmĭnātĭo, ōnis, f. [denomino], rhetor. t. t., the substitution of the name of an object for that of another to which it has some relation, as the name of the cause for that of the effect, of the property for that of the substance, etc.; a metonymy, Auct. Her. 4, 32; cf. Quint. 8, 6, 23 sq., and immutatio.