vāllō āvī, ātus, āre vallum, to fortify with a rampart, surround with palisades, intrench, circumvallate: castra, L.: noctem, i. e. intrench themselves at night, Ta.

—Fig., to fortify, protect, defend: Pontus et naturā et regione vallatus: haec omnia quasi saepimento aliquo vallabit disserendi ratione: Catilina vallatus sicariis.