Semidiurnal
Pronunciation : Sem`i*di*ur"nal
Part of Speech : a.
Definition : 1. Pertaining to, or accomplished in, half a day, or twelve hours; occurring twice every day.
2. Pertaining to, or traversed in, six hours, or in half the time between the rising and setting of a heavenly body; as, a semidiurnal arc.
Source : Webster's Unabridged Dictionary, 1913
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