One celestial body obscures another.

synonym: eclipse.

Roget 421: darkness etc. adj., absence of light; blackness etc. (dark color) 431; obscurity, gloom, murk; dusk etc. (dimness) 422.    Cimmerian darkness^†, Stygian darkness, Egyptian darkness; night; midnight; dead of night, witching hour of night, witching time of night; blind man's holiday; darkness visible, darkness that can be felt; palpable obscure; Erebus [Lat.]; the jaws of darkness" [Midsummer Night's Dream]; sablevested night" [Milton]. shade, shadow, umbra, penumbra; sciagraphy^†.    obscuration; occultation, adumbration, obumbration^†; obtenebration^†, offuscation^†, caligation^†; extinction; eclipse, total eclipse; gathering of the clouds.    shading; distribution of shade; chiaroscuro etc. (light) 420.    noctivagation^†.    [perfectly black objects] black body; hohlraum [Phys.]; black hole; dark star; dark matter, cold dark matter.    ... show more

Roget 449: disappearance, evanescence, eclipse, occultation.    departure etc. 293; exit; vanishing point; dissolving views.   

Roget 528: concealment; hiding etc. v.; occultation, mystification.    seal of secrecy; screen etc. 530; disguise etc. 530; masquerade; masked battery; hiding place etc. 530; cryptography, steganography^†; freemasonry.    stealth, stealthiness, sneakiness; obreption^†; slyness etc. (cunning) 702.    latitancy^†, latitation^†; seclusion etc. 893; privacy, secrecy, secretness^†; incognita.    reticence; reserve; mental reserve, reservation; arriere pensee [Fr.], suppression, evasion, white lie, misprision; silence etc. (taciturnity) 585; suppression of truth etc. 544; underhand dealing; closeness, secretiveness etc. adj.; mystery.    latency etc. 526; snake in the grass; secret etc. 533; stowaway.    ... show more

Dutch: Eclipse, eclips, immersie, verduistering
Polish: zaćmienie