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sid·dur

(sĭdər, -r′)

n. pl. sid·du·rim (sĭ-drĭm, sĭ′d-rĭm)

A Jewish prayer book for everyday use.

[Mishnaic Hebrew siddûr, arrangement, from siddēr, to arrange, derived stem of sādar; see sdr in the Appendix of Semitic roots.]

Indo-European & Semitic Roots Appendices

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:

Indo-European Roots

Semitic Roots

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.

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