saros
Concise Oxford English Dictionary © 2008 Oxford University Press:
saros /ˈsɛːrɒs/
▶noun Astronomy a period of about 18 years between repetitions of solar and lunar eclipses.
– origin C19: from Gk, from Babylonian šār(u) ‘3,600 (years)’, the sense appar. based on a misinterpretation of the number.
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