siddur definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
siddur definition by American Heritage Dictionary
noun pl. sid·du·rim Judaism
A prayer book containing prayers for the various days of the year.
Origin: Mishnaic Hebrew siddûr, arrangement, from siddēr, to arrange, derived stem of sādar; see sdr in Semitic roots.