1. The seventh day of the week, Saturday, observed as the day of rest and worship in Judaism and some Christian sects.
2. The first day of the week, Sunday, observed as the day of rest and worship in most forms of Christianity.
[Middle English sabat, from Old French sabbat and Old English sabat, both from Latin sabbatum, from Greek sabbaton, from Hebrew šabbāt, from šābat, to cease, rest; see šbt in the Appendix of Semitic roots.]
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Indo-European & Semitic Roots Appendicies
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.