coating vs scumble

coating and scumble both are nouns.

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

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

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

coating (noun)	scumble (noun)
the work of applying something	the application of very thin coat of color over the surface of a picture
a thin layer covering something
a heavy fabric suitable for coats
a decorative texture or appearance of a surface (or the substance that gives it that appearance)