ūsŭārĭus — Lewis & Short
ūsŭārĭus, a, um, adj.id.,
I of or belonging to use, usuary, viz.,
I Pass., that is used, made use of:
servus,i. e. whom one has the use of, but does not own, Dig. 7, 8, 14; Gell. 4, 1, 23.—
II Act., as subst.: ūsŭā-rĭus, ii, m., one who uses or has the use of a thing, but no right of property in it:
usus aquae personalis est: et ideo ad heredem usuarii transmitti non potest,Dig. 7, 8, 21:
eadem et in usuario dicenda sunt,ib. 7, 1, 13, § 2.