Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
mĭnūtĭo, ōnis, f. [minuo], a lessening, diminishing (post-Aug.); trop., opp. incrementum, Quint. 8, 4, 28: rerum, id. 6, 3, 52: capitis, i. e. deminutio, Gell. 1, 12, 9; Dig. 4, 5, 1; 4, 5, 5: sanguinis, blood-letting, bleeding, Veg. Vet. 1, 28, 1; so, minutio alone: cum praescriptis minutionis observantiis, id. ib. 1, 17, 13.