melodious vs tuneful

melodious and tuneful both are adjectives.

Word	Noun	Adjective	Verb	Adverb
melodious	No	Yes	No	No
tuneful	No	Yes	No	No

As adjectives, melodious and tuneful are synonyms defined as:

melodious and tuneful: having a musical sound; especially a pleasing tune

melodious (adjective)	tuneful (adjective)
containing or constituting or characterized by pleasing melody	having a musical sound; especially a pleasing tune
having a musical sound; especially a pleasing tune