lūstrum ī, n
3 LV-,
a purificatory sacrifice, expiatory offering, lustration
(for the whole people by the censors at the end of their term of five
years): lustrum condidit,
made the lustral sacrifice
: sub lustrum censeri,
at the close of the census.—A period of five years, lustrum
: octavum, H.: hoc ipso lustro: superioris lustri reliqua.—
A period of four years
(of the Julian calendar), O.