Lewis Short
(adjective) : sub-tristis, e
* Somewhat sad or sorrowful (ante- and post-class.): subtristis visus est mihi,Ter. And. 2, 6, 16; Hier. Ep. 107, 9.—Comp.: cera subtristior,Hier. Ep. 60, 1.
Charlton T. Lewis, Charles Short, A Latin Dictionary