Sabbath

n. Saturday, day of rest and religious observance among Jews and some Christian sects; Sunday, day of rest and religious observance for most Christians; period of rest

The Sabbath (or Sabbat) is a weekly day of rest and/or worship that is observed in the Judeo-Christian faiths. The term derives from the Hebrew shavat, "(to) rest". It originates from the biblical account of the last day of creation, and was repeated as part of the Ten Commandments. A number of other religions have a similar practice, and the term has also been imported into secular usage.
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Noun
1. a day of rest and worship: Sunday for most Christians; Saturday for the Jews and a few Christians; Friday for Muslims
(hypernym) rest day, day of rest

(n.)
The seventh year, observed among the Israelites as one of rest and festival.
  

(n.)
Fig.: A time of rest or repose; intermission of pain, effort, sorrow, or the like.
  

(n.)
A season or day of rest; one day in seven appointed for rest or worship, the observance of which was enjoined upon the Jews in the Decalogue, and has been continued by the Christian church with a transference of the day observed from the last to the first day of the week, which is called also Lord's Day.
  

Sabbath shabbath (Hebrew) [from shabath voluntary repose] The seventh day of the week, appointed in the Hebrew decalog a day of rest, to be observed by the Jews -- now equivalent to Saturday, Saturn's day. The intimate relationship of ancient Jewish mystical and theological thought with the planet Saturn as the outermost then recognized of the planetary system provides a key.
In the deeper sense Sabbath "means rest or Nirvana. It is not the seventh day after six days but a period the duration of which equals that of the seven 'days' or any period made up of seven parts" (SD 1:240).