Lewis Short
Castălĭa | Castă-lĭus, a, um | Castălis, ĭdis (noun F.f) : Κασταλία
* A fountain on Parnassus, sacred to Apollo and the Muses, Liv. Andron. ap. Fest. p. 310, b Müll.; Verg. G. 3, 293; Hor. C. 3, 4, 61; Stat. Th. 1, 698.
* Hence the adjj.
* Castalian: fons,Plin. 4, 3, 4, § 8; Sen. Oedip. 229; cf. fontes,Stat. Th. 1, 565: arbor,the laurel,Prop. 3 (4), 3, 13.hence, umbra,Tib. 3, 1, 16: antrum,i. e. the cave of the oracle at Delphi,Ov. M. 3, 14.
* Castalian: unda,Mart. 9, 19 fin.: sorores,i. e. the Muses,id. 4, 14; also as subst.: Castalidum grex,id. 7, 12, 10.
Charlton T. Lewis, Charles Short, A Latin Dictionary