Definition - What does Bhakti mean?
Bhakti means the path of loving devotion to a particular god or deity, which, it is believed, leads to salvation or nirvana. From the Sanskrit root word bhaj, meaning "to adore or worship God," bhakti forms one of the paths of yoga: Bhakti yoga.
Bhakti is also sometimes described as “love for love’s sake."
Yogapedia explains Bhakti
The term, bhakti, can also be interpreted as "devotional service." When one expresses true devotion, he/she is selfless in his/her desire to please the beloved. It is thought that by loving and serving a god or deity, one will also love and serve the Divine in everything, thus finding salvation.
Bhakti is discussed in Hindu sacred texts such as the Upanishads and the Bhagavad Gita. It is believed that bhakti is the foundation for all religious paths.