indulging vs excess

indulging and excess both are nouns.

Word	Noun	Adjective	Verb	Adverb
indulging	Yes	No	No	No
excess	Yes	Yes	No	No

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

Other hyponyms of indulging include intemperance, intemperateness, self-indulgence, overindulgence, binge, orgy, splurge.

indulging (noun)	excess (noun)
the act of indulging or gratifying a desire	excessive indulgence
	immoderation as a consequence of going beyond sufficient or permitted limits
	a quantity much larger than is needed
	the state of being more than full

indulging (adjective)	excess (adjective)
	more than is needed, desired, or required