motive vs melodic theme

motive and melodic theme both are nouns.

Word	Noun	Adjective	Verb	Adverb
motive	Yes	Yes	No	No
melodic theme	Yes	No	No	No

As nouns, melodic theme is a hypernym of motive; that is, melodic theme is a word with a broader meaning than motive:

Other hypernyms of motive include idea, musical theme, theme.

motive (noun)	melodic theme (noun)
the psychological feature that arouses an organism to action toward a desired goal; the reason for the action; that which gives purpose and direction to behavior	(music) melodic subject of a musical composition
a design or figure that consists of recurring shapes or colors, as in architecture or decoration
a theme that is repeated or elaborated in a piece of music

motive (adjective)	melodic theme (adjective)
causing or able to cause motion
impelling to action