Dictionary

sidereal

adjective si·de·re·al \sī-ˈdir-ē-əl, sə-\

Definition of SIDEREAL

:  of, relating to, or expressed in relation to stars or constellations :  astral
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Origin of SIDEREAL

Latin sidereus, from sider-, sidus star, constellation
First Known Use: 1647

Other Astronomy Terms

gibbous, nadir, nebulous, penumbra, retrograde, syzygy, wane, wax, zenith
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