wail vs howl

wail and howl both are nouns.

Word	Noun	Adjective	Verb	Adverb
wail	Yes	No	Yes	No
howl	Yes	No	Yes	No

As verbs, wail and howl are synonyms defined as:

Other synonyms of wail include roar, ululate, yaup, yawl.

wail (noun)	howl (noun)
a cry of sorrow and grief	a long loud emotional utterance
	a loud sustained noise resembling the cry of a hound
	the long plaintive cry of a hound or a wolf

wail (verb)	howl (verb)
cry weakly or softly	laugh unrestrainedly and heartily
emit long loud cries	make a loud noise, as of wind, water, or vehicles
	emit long loud cries
	cry loudly, as of animals