pervigilium

pervigilium ī, n

pervigil, a devotional watching, vigil : castra pervigilio neglecta, L., Ta.

pervigilium
pervĭgĭlĭum, ii, n. [pervigil], a watching all night, a remaining awake or sitting up all night long...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.