castellum ī, n dim. castrum, a castle, fort, citadel, fortress, stronghold: crebra, Cs.: castellis ab ingressione propulsari: multa capere, S.: montana castella, V.: castella communit, towers (on a wall), Cs.: castella facta, posts (for guards), Cs.

— Poet.: Norica Castella in tumulis, i. e. mountain homes, V.

—Fig., a shelter, stronghold, defence, refuge: latrocinii: castellum omnium scelerum, L.