Meaning of “cloud” - Learner’s Dictionary

cloud

noun uk us /klaʊd/
WEATHER [ C, U ]

A2 a white or grey mass that floats in the sky, made of small water drops:

rain/storm clouds
The entire region is covered in thick cloud.
DIRTY AIR [ C ]

B2 a mass of gas or very small pieces of something floating in the air:

a cloud of dust/smoke
cloudless adjective

without clouds

(Definition of “cloud noun” from the Cambridge Learner’s Dictionary © Cambridge University Press)