1. (用来保护或隐藏的)覆盖物，遮盖物
A covering is a layer of something that protects or hides something else.

1. the work of applying something

e.g. the doctor prescribed a topical application of iodine
a complete bleach requires several applications
the surface was ready for a coating of paint

Synonym: applicationcoating

2. the act of protecting something by covering it

3. the act of concealing the existence of something by obstructing the view of it

e.g. the cover concealed their guns from enemy aircraft

Synonym: coverscreeningmasking

4. an artifact that covers something else (usually to protect or shelter or conceal it)

5. a natural object that covers or envelops

e.g. under a covering of dust
the fox was flushed from its cover

Synonym: natural coveringcover