Occultation n. : The hiding of a heavenly body from sight by the intervention of some other of the heavenly bodies; -- applied especially to eclipses of stars and planets by the moon, and to the eclipses of satellites of planets by their primaries.

Occultation n. : Fig.: The state of being occult.

Example:
When is the asteroid Occultation of September 11-12?

Taxonomy
occultation, planets, transits, occults, transit of Mercury, satellite, eclipse, by the Moon, satellite of Jupiter, the Moon, moon, lunar occultations, planetary transits, Sun, surface of the Earth, star, dwarf planet, Saturn.

Defination from the web:
Occultation is a term used to designate the hidden state of the Imam of the Time. See also occult (disambiguation) ... An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer. ...