From cloudy + -ness.

cloudiness

1. Of the sky, weather, etc.: the state of being cloudy.

   Expect considerable cloudiness with occasional rain showers.

   • 1598–1599 (first performance), William Shakespeare, “Much Adoe about Nothing”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC ↗, [Act V, scene iv], page 121 ↗, column 1:

     [W]hy vvhat's the matter? / That you haue ſuch a Februarie face, / So full of froſt, of ſtorme, and clovvdineſſe.

     A figurative use.

2. Of a liquid: the property of being murky.

   Cloudiness in the water is most often caused in new aquariums by white bacteria.

3. (figurative) Of information, a writing style, etc.: the property of being obscure.

   Avoid cloudiness in your essay-writing.

• cloud ceiling
• cloud cover

• Italian: nuvolosità, copertura
• Russian: о́блачность
• Spanish: nubosidad

• French: nébulosité
• Italian: torbidezza