rude vs underbred

rude and underbred both are adjectives.

Word	Noun	Adjective	Verb	Adverb
rude	No	Yes	No	No
underbred	No	Yes	No	No

As adjectives, rude and underbred are synonyms defined as:

Other synonyms of rude include bounderish, ill-bred, lowbred, yokelish.

rude (adjective)	underbred (adjective)
lacking civility or good manners	of inferior or mixed breed
belonging to an early stage of technical development; characterized by simplicity and (often) crudeness	(of persons) lacking in refinement or grace
socially incorrect in behavior
(used especially of commodities) being unprocessed or manufactured using only simple or minimal processes
(of persons) lacking in refinement or grace