The term colure (from the Greek kólouros = tailless) denotes two special meridians on the celestial sphere.

The meridian that intersects the solstitial points, i.e., the two points touched by the Sun at the summer solstice and winter solstice, when at noon it appears respectively at its maximum altitude and minimum altitude above the horizon.

The meridian that intersects the equinoctial points, i.e., the two points in which the Sun appears at the spring equinox and autumn equinox, when day and night are of exactly equal length. By construction, the colures and the celestial equator intersect the celestial sphere on perpendicular planes.