|equinoctial, Also called: equinoctial circle the great circle lying on the celestial sphere the plane of which is perpendicular to the line joining the north and south celestial poles|
|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|a children's mummer's parade, as on the Fourth of July, with prizes for the best costumes.|
A great circle separating the northern and southern hemispheres of the celestial sphere and lying in the same plane as the Earth's equator. The celestial equator is a projection of the Earth's equator outward onto the celestial sphere and is used as the reference point in determining a celestial body's declination.