sid·dur (sĭdər, -r′)
n. pl. sid·du·rim (sĭ-drĭm, 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.]
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