Church
A New Testament church of the Lord Jesus Christ is an autonomous local congregation of baptized believers, associated by covenant in the faith and fellowship of the gospel; observing the two ordinances of Christ, governed by His laws, exercising the gifts, rights, and privileges invested in them by His Word, and seeking to extend the gospel to the ends of the earth.
We sometimes distinguish between a church (a local body of believers who share some level of fellowship) and The Church (the universal collection of God's people everywhere).