indulge vs wallow

indulge is not a noun while wallow is a noun.

Word	Noun	Adjective	Verb	Adverb
indulge	No	No	Yes	No
wallow	Yes	No	Yes	No

As verbs, wallow is a hyponym of indulge; that is, wallow is a word with a more specific, narrower meaning than indulge:

indulge: give free rein to
wallow: devote oneself entirely to something; indulge in to an immoderate degree, usually with pleasure

indulge (noun)	wallow (noun)
	an indolent or clumsy rolling about
	a puddle where animals go to wallow

indulge (verb)	wallow (verb)
yield (to); give satisfaction to	delight greatly in
enjoy to excess	devote oneself entirely to something; indulge in to an immoderate degree, usually with pleasure
treat with excessive indulgence	be ecstatic with joy
give free rein to	roll around
	rise up as if in waves