1) Day of rest 2) Rest day 
one who keeps the sabbath strictly
• (a.) Of or pertaining to the Sabbath, or the tenets of Sabbatarians. • (n.) A strict observer of the Sabbath. • (n.) One who regards and keeps the seventh day of the week as holy, agreeably to the letter of the fourth commandment in the Decalogue.
Sab`ba·ta'ri·an noun [ Latin Sabbatarius : confer French sabbataire . See Sabbath .] 1. One who regards and keeps the seventh day of the week as holy, agreeably to the letter of the fourth commandment in the Decalogue. » There were Christians in the early church who...
[adj] - pertaining to the Sabbath and its observance 2. [n] - one who observes Saturday as the Sabbath (as in Judaism)
adjective pertaining to the Sabbath and its observance