tears vs wailing

tears and wailing both are nouns.

Word	Noun	Adjective	Verb	Adverb
tears	Yes	No	No	No
wailing	Yes	Yes	No	No

As nouns, wailing is a hyponym of tears; that is, wailing is a word with a more specific, narrower meaning than tears:

tears: the process of shedding tears (usually accompanied by sobs or other inarticulate sounds)
wailing: loud cries made while weeping

Other hyponyms of tears include snivel, sniveling, sob, sobbing, bawling.

tears (noun)	wailing (noun)
the process of shedding tears (usually accompanied by sobs or other inarticulate sounds)	loud cries made while weeping

tears (adjective)	wailing (adjective)
	vocally expressing grief or sorrow or resembling such expression