1. noun /ɛˈklɪps,iˈklɪps/
a) An astronomical alignment in which 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 object onto the other object.
b) A seasonal state of plumage in some birds, notably ducks, adopted temporarily after the breeding season and characterised by a dull and scruffy appearance.
2. verb /ɛˈklɪps,iˈklɪps/
a) Of astronomical bodies, to cause an eclipse.
The Moon eclipsed the Sun.
b) To overshadow; to be better or more noticeable than.
The student’s skills soon eclipsed those of his teacher.
Wikipedia foundation.