Dicionário

Lustrum

Webster's Dictionary 1913

Lus″trum (?), n.; pl. E. Lustrums (#), L. Lustra (#). [L. Cf. 2d & 3d Luster.] A lustration or purification, especially the purification of the whole Roman people, which was made by the censors once in five years. Hence: A period of five years.