covering vs scumble

covering and scumble both are nouns.

Word	Noun	Adjective	Verb	Adverb
covering	Yes	No	No	No
scumble	Yes	No	No	No

As nouns, scumble is a hyponym of covering; that is, scumble is a word with a more specific, narrower meaning than covering:

covering: the work of applying something
scumble: the application of very thin coat of color over the surface of a picture

covering (noun)	scumble (noun)
the act of protecting something by covering it	the application of very thin coat of color over the surface of a picture
the work of applying something
the act of concealing the existence of something by obstructing the view of it
an artifact that covers something else (usually to protect or shelter or conceal it)
a natural object that covers or envelops