The Collaborative International Dictionary of English v.0.48:

Seventh \Sev"enth\, a. [From Seven: cf. AS. seofo[eth]a.]
   1. Next in order after the sixth;; coming after six others.
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            On the seventh day, God ended his work which he had
            made; and he rested on the seventh day from all his
            work which he had made.               --Gen. ii. 2.
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   2. Constituting or being one of seven equal parts into which
      anything is divided; as, the seventh part.
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   Seventh day, the seventh day of the week; Saturday.

   Seventh-day Baptists. See under Baptist.
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