gnarl vs croak

gnarl and croak both are nouns.

Word	Noun	Adjective	Verb	Adverb
gnarl	Yes	No	Yes	No
croak	Yes	No	Yes	No

As verbs, gnarl and croak are synonyms defined as:

Other synonyms of gnarl include grumble, murmur, mutter.

gnarl (noun)	croak (noun)
something twisted and tight and swollen	a harsh hoarse utterance (as of a frog)

gnarl (verb)	croak (verb)
make complaining remarks or noises under one's breath	pass from physical life and lose all bodily attributes and functions necessary to sustain life
twist into a state of deformity	make complaining remarks or noises under one's breath
	utter a hoarse sound, like a raven