Opusculum | Webster's Dictionary of the English Language

opusculum
ŏpuscŭlum, i, n. dim. [1. opus], a little work (class.): Myrmecides minutorum opusculorum fabricato...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.
opusculum
opusculum ī, n dim.1 opus, a little work : minutorum opusculorum fabricator: Cassi Parmensis, H. ...

An Elementary Latin Dictionary