ecliptic Astronomy [ ɪ'klɪptɪk ]
■ noun a great circle on the celestial sphere representing the sun's apparent path during the year, so called because lunar and solar eclipses can only occur when the moon crosses it.
■ adjective of eclipses or the ecliptic.
Origin
ME: via L. from Gk ekleiptikos , from ekleipein (see eclipse ).