Either of two great circles of the celestial sphere that passes through the poles and meets the ecliptic at either the solstice points (the solstitial colure) or the equinox points (the equinoctial colure).
From L. colurus, from Gk. kolouros "dock-tailed," from kol(os) "docked" + -ouros "-tailed," from oura "tail;" so called because the lower part is permanently hidden beneath the horizon.
Koldom, from Mod.Pers. kol "docked, short," most probably cognate with the Gk. term, as above, + dom(b) "tail," Av. duma- "tail." Recorded in classical dictionaries, kol has several variants in a large number of dialects: kola, kalta, kel, kelma, koc, kall, kor, kul in Gilaki, Tâleši, Lori, Malâyeri, Hamedâni, Qâeni, and others, cf. Av. kaurva- "bald, docked," kaurvôduma- "with a bald tail," kaurvôgaoša- "with bald ears."
Fr.: colure d'équinoxe
The great circle of the celestial sphere through the celestial poles and equinoxes; the hour circle of the vernal equinox. → colure.
Fr.: colure de solstice
The great circle of the celestial sphere which passes through the poles of the celestial equator and the solstice points. → equinoctial colure.