libelous vs calumnious

libelous and calumnious both are adjectives.

Word	Noun	Adjective	Verb	Adverb
libelous	No	Yes	No	No
calumnious	No	Yes	No	No

As adjectives, libelous and calumnious are synonyms defined as:

libelous and calumnious: (used of statements) harmful and often untrue; tending to discredit or malign

Other synonyms of libelous include calumniatory, defamatory, denigrating, denigrative, denigratory, libellous, slanderous.

libelous (adjective)	calumnious (adjective)
(used of statements) harmful and often untrue; tending to discredit or malign	(used of statements) harmful and often untrue; tending to discredit or malign