croak vs drown

croak is a noun but drown is not a noun.

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

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

croak: pass from physical life and lose all bodily attributes and functions necessary to sustain life
drown: die from being submerged in water, getting water into the lungs, and asphyxiating

Other hyponyms of croak include abort, asphyxiate, stifle, suffocate, buy it, pip out, predecease, famish, starve, fall, succumb, yield.

croak (noun)	drown (noun)
a harsh hoarse utterance (as of a frog)

croak (verb)	drown (verb)
pass from physical life and lose all bodily attributes and functions necessary to sustain life	die from being submerged in water, getting water into the lungs, and asphyxiating
make complaining remarks or noises under one's breath	kill by submerging in water
utter a hoarse sound, like a raven	get rid of as if by submerging
	cover completely or make imperceptible
	be in danger of dying from submersion in a liquid and asphyxiation
	be covered with or submerged in a liquid