Lewis & Short

spĕcŭlātīvus, a, um, adj. [speculor], speculative (late Lat.): philosophia, Boëth. ap. Porphyr. Dial. 1, p. 2.
Hence, subst.: spĕcŭlātīva, ae, f., = contemplativa (sc. philosophia), Cassiod. Var. 1, 45.