lament vs bewail

lament is a noun but bewail is not a noun.

Word	Noun	Adjective	Verb	Adverb
lament	Yes	No	Yes	No
bewail	No	No	Yes	No

As verbs, lament and bewail are synonyms defined as:

Other synonyms of lament include bemoan, deplore.

lament (noun)	bewail (noun)
a mournful poem; a lament for the dead
a song or hymn of mourning composed or performed as a memorial to a dead person
a cry of sorrow and grief

lament (verb)	bewail (verb)
regret strongly	regret strongly
express grief verbally