Word Study
saros
CIDE DICTIONARY
saros, n. [NL., fr. Gr. ].
A Chaldean astronomical period or cycle, the length of which has been variously estimated from 3,600 years to 3,600 days, or a little short of 10 years. Brande & C. [1913 Webster]
OXFORD DICTIONARY
saros, n. Astron. a period of about 18 years between repetitions of eclipses.
Etymology
Gk f. Babylonian sar(u) 3,600 (years)
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