o·mer (ōmər, ōmĕr)
1. An ancient Hebrew unit of dry measure equal to a tenth of an ephah, about 3.5 liters (3.7 quarts).
a. An offering of a sheaf or an omer of the first harvest of barley to a priest in the Temple on the second day of Passover.
b. Omer A 49-day liturgical season, originally a harvest festival, from the second day of Passover to the first day of Shavuot, during which marriages are prohibited and signs of mourning are observed.
[Hebrew 'ōmer; see ġmr in the Appendix of Semitic roots. Sense 2b, from the offering of a sheaf of barley on the second day of Passover.]
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