MILLEN'IUM, noun [Latin mille, a thousand, and annus, year.] A thousand years; a word used to denote the thousand years mentioned in Revelations 20. during which period Satan shall be bound and restrained from seducing men to sin, and Christ shall reign on earth with his saints.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI