Webster’s Revised Unabridged Dictionary · 1913
Congregational
Con′gre·ga′tion·al (·al), a. 1. Of or pertaining to a congregation; conducted, or participated in, by a congregation; as, congregational singing.
2. Belonging to the system of Congregationalism, or to Congregationalist; holding to the faith and polity of Congregationalism; as, a Congregational church.