bhakti vs devotion

bhakti and devotion both are nouns.

Word	Noun	Adjective	Verb	Adverb
bhakti	Yes	No	No	No
devotion	Yes	No	No	No

As nouns, devotion is a hypernym of bhakti; that is, devotion is a word with a broader meaning than bhakti:

bhakti: (Hinduism) loving devotion to a deity leading to salvation and nirvana; open to all persons independent of caste or sex
devotion: (usually plural) religious observance or prayers (usually spoken silently)

bhakti (noun)	devotion (noun)
(Hinduism) loving devotion to a deity leading to salvation and nirvana; open to all persons independent of caste or sex	(usually plural) religious observance or prayers (usually spoken silently)
	commitment to some purpose
	religious zeal; the willingness to serve God
	feelings of ardent love