Revival in one word means a reawakening.
When revival occurs in the life of an individual or a gathering of people, it means the Holy Spirit has evidently come afresh upon everyone. PRAYER precedes revival. It is the vehicle which ushers in revival.
Revival requires brokenness - Isaiah 57:15
For thus saith the high and lofty One that inhabiteth eternity, whose name is Holy; I dwell in the high and holy place, with him also that is of a contrite and humble spirit, to revive the spirit of the humble, and to revive the heart of the contrite ones.
Revival releases upon man, the gifts of the Spirit.
Revival is brings you to the place of sacrifice - Luke 22:33
[33] And he said unto him, Lord, I am ready to go with thee, both into prison, and to death.