colure
/kəˈlʊr/
noun
- Either of two great circles of the celestial sphere that intersect at the celestial poles: the equinoctial colure (passing through the equinoxes) and the solstitial colure (passing through the solstices).
- The equinoctial colure passes through the March and September equinox points.
- Astronomers use the colures to help map the positions of stars.
- The solstitial colure is an imaginary line in the sky that goes through the summer and winter solstices.