ebb vs ebbing

ebb and ebbing both are nouns.

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

As nouns, ebb and ebbing are synonyms defined as:

ebb and ebbing: a gradual decline (in size or strength or power or number)

Other synonyms of ebb include wane.

ebb (noun)	ebbing (noun)
the outward flow of the tide	a gradual decline (in size or strength or power or number)
a gradual decline (in size or strength or power or number)

ebb (verb)	ebbing (verb)
fall away or decline
hem in fish with stakes and nets so as to prevent them from going back into the sea with the ebb
flow back or recede