The period of time following the return of Christ described in Revelation 20:1-10. The name is derived from the reference to a thousand years. There are numerous views surrounding what occurs during this time and when it actually happens. Likewise, some believe this time period to be a literal thousand years while others see it as a symbolic time period denoting an indefinite long period of time.
During this period of time, Satan is bound and resurrected saints reign with Christ. Once again, depending on the view one adopts, these events could be literal or figurative. The amillennial view sees this as occurring today as Christ reigns within the hearts of believers. Other views see this as still future.
See also premillennialism and postmillennialism for different views concerning the Millennial Kingdom.
For further discussion see the article on the Millennial Kingdom.