Word Study
rubaiyat
CIDE DICTIONARY
rubaiyat, n. pl. [Ar. rubā'iyāh quatrian, pl. of rubā'iy having four radicals, fr. rubā' four.].
Quatrians; as, the Rubaiyat of Omar Khayyam . Sometimes in pl. construed as sing. , a poem in such stanzas. [Webster 1913 Suppl.]
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