eclipse /ɪˈklɪps/noun 4verb 3forms 5 noun4 •An alignment of astronomical objects whereby one object comes between the observer (or notional observer) and another object, thus obscuring the latter. •Especially, an alignment whereby a planetary object (for example, the Moon) comes between the Sun and another planetary object (for example, the Earth), resulting in a shadow being cast by the middle planetary object onto the other planetary object. •Obscurity, decline, downfall.All the posterity of our first parents suffered a perpetual eclipse of spiritual life. — 1618 •A seasonal state of plumage in some birds, notably ducks, adopted temporarily after the breeding season and characterised by a dull and scruffy appearance. verb3 •Of astronomical or atmospheric bodies, to cause an eclipse.The Moon eclipsed the Sun. •(figurative) To overshadow; to be better or more noticeable than.For, till I see them here, by doubtful fear / My joy of liberty is half eclips'd. — 1591 •To undergo eclipsis. formseclipsed · eclipsing · eclipses · eclipseth · eclipsest