Lustrum

A lūstrum (IPA: [ˈluːs̠t̪rʊ̃ˑ], plural lūstra) was a term for a five-year period in Ancient Rome.

It is distinct from the homograph lustrum (/ˈlʊstrəm/ LUSS-trəm): a haunt of wild beasts (and figuratively, a den of vice), plural lustra (/ˈlʊstrɑː/ LUUS-trah).[1]

  1. ^ Oxford Latin Desk Dictionary (2005). Oxford: Oxford University Press. pp. vii, 109