howl vs wail

howl and wail both are nouns.

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

As verbs, howl and wail are synonyms defined as:

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

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

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