diminution vs ebbing

diminution and ebbing both are nouns.

Word	Noun	Adjective	Verb	Adverb
diminution	Yes	No	No	No
ebbing	Yes	No	No	No

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

diminution (noun)	ebbing (noun)
the act of decreasing or reducing something	a gradual decline (in size or strength or power or number)
the statement of a theme in notes of lesser duration (usually half the length of the original)
change toward something smaller or lower