Lewis Short
(adjective) : sēmuncĭārĭus, a, um, id.
* Amounting to a half-ounce (one twentyfourth of an as): semunciarium tantum ex unciario faenus factum, one twenty-fourth of an as upon each as, for a year of ten months, or, acc. to our mode of computation, five per cent. for a full year, Liv. 7, 27, 3; cf. id. 7, 16, 1: asses,weighing half an ounce,Plin. 33, 3, 13, § 46 Jahn.
Charlton T. Lewis, Charles Short, A Latin Dictionary