sabbatarian

A person who regards and keeps the seventh day of the week ("Saturday", the Israelite or Jewish Sabbath) as holy in conformity with the fourth commandment of the Decalogue, such as an Orthodox Jew, Seventh-day Adventist, Seventh Day Baptist

A person who regards and keeps the first day of the week as holy and often considers it as a replacement for the seventh-day Sabbath, a Sunday-keeper.

During the sixties [1860s] the Sabbatarians were particularly active in their attacks on Sunday excursions, and this had an effect both on the companies and the public.

A person who favors the strict observance of the Sabbath (either the sixth, seventh, or first day of the week).

A member of a non-Jewish religious sect originating in Russia distinguished by observance of Jewish rites and festivals including Saturday as the day of rest.

Of or pertaining to the Sabbath, or the tenets of Sabbatarians.

The Newcastle & Carlisle Railway announced a special Sunday excursion from Newcastle to Carlisle for August 29, 1841, and immediately ran up against strong Sabbatarian opposition.

Alternative letter-case form of Sabbatarian.