bacchanal vs bacchanalian

bacchanal is a noun but bacchanalian is not a noun.

Word	Noun	Adjective	Verb	Adverb
bacchanal	Yes	Yes	No	No
bacchanalian	No	Yes	No	No

As adjectives, bacchanal and bacchanalian are synonyms defined as:

Other synonyms of bacchanal include bacchic, carousing, orgiastic.

bacchanal (noun)	bacchanalian (noun)
a wild gathering involving excessive drinking and promiscuity
someone who engages in drinking bouts
a drunken reveller; a devotee of Bacchus

bacchanal (adjective)	bacchanalian (adjective)
used of riotously drunken merrymaking	used of riotously drunken merrymaking