harmonic vs harmonious

harmonic is a noun but harmonious is not a noun.

Word	Noun	Adjective	Verb	Adverb
harmonic	Yes	Yes	No	No
harmonious	No	Yes	No	No

harmonic (noun)	harmonious (noun)
any of a series of musical tones whose frequencies are integral multiples of the frequency of a fundamental
a tone that is a component of a complex sound

harmonic (adjective)	harmonious (adjective)
of or relating to harmony as distinct from melody and rhythm	musically pleasing
of or relating to the branch of acoustics that studies the composition of musical sounds	exhibiting equivalence or correspondence among constituents of an entity or between different entities
of or relating to harmonics	existing together in harmony
involving or characterized by harmony	suitable and fitting
relating to vibrations that occur as a result of vibrations in a nearby body