Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ūsĭo, ōnis, f. [utor], use (ante- and postclass.): domini usioni recipitur, Cato, R. R. 149, 2: quae tibi usioni supererunt, id. ib. 38, 4: usioni quod satis esset, Varr. ap. Non. 231, 6: usionis gratiā, Scaevola ap. Gell. 4, 1, 17: usionis causā, Dig. 34, 2, 28.
Plur., Arn. 7, p. 238 dub.