harmonious vs symmetrical

harmonious and symmetrical both are adjectives.

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

As adjectives, harmonious and symmetrical are synonyms defined as:

harmonious and symmetrical: exhibiting equivalence or correspondence among constituents of an entity or between different entities

Other synonyms of harmonious include proportionate.

harmonious (adjective)	symmetrical (adjective)
musically pleasing	having similarity in size, shape, and relative position of corresponding parts
exhibiting equivalence or correspondence among constituents of an entity or between different entities	exhibiting equivalence or correspondence among constituents of an entity or between different entities
existing together in harmony
suitable and fitting