Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
sŭbĭces, um, f. [subicio], underlayers, supports: Ennius in tragoediā, quae Achilles inscribitur, pro aëre alto ponit, qui caelo subjectus est, in his versibus: per ego deum sublimas subices umidas, Unde oritur imber, sonitu saevo et strepitu, Gell. 4, 17, 14; cf. Fest. p. 305 Müll., and Non. 168, 33 (Trag. v. 5 Vahl.).