one celestial body obscures another
"During a solar eclipse, the moon moves between Earth and the sun to obscure its light."
An alignment of astronomical objects whereby one object comes between the observer (or notional observer) and another object, thus obscuring the latter.
"During a solar eclipse, the Moon passes directly between Earth and the Sun, casting its shadow on our planet and briefly hiding the star from view."
In plain English: An eclipse happens when one celestial object blocks the light from another, making it disappear temporarily from view.
"The solar eclipse was visible across most of North America yesterday."
Usage: Use this word for any event where a celestial body blocks light from reaching an observer or another object, such as when the moon passes between Earth and the sun. Avoid using it metaphorically unless you are specifically describing one thing completely overshadowing another in importance.
be greater in significance than
"the tragedy overshadowed the couple's happiness"
Of astronomical bodies, to cause an eclipse.
"The moon passed directly between Earth and the sun to completely eclipse it."
In plain English: To eclipse something means to make it seem less important by being much better than it is.
"The new technology completely eclipsed all previous methods in efficiency."
The word "eclipse" comes from the Latin eclipsis, which was borrowed from Ancient Greek for the same meaning. It originally described something that is abandoned or vanishes, derived from a verb meaning "to leave behind."