CC Madhya 24.30
eka — ‘sādhana’, ‘prema-bhakti’ — nava prakāra
“There are ten meanings for the word ‘bhakti’ [‘devotional service’]. One is sādhana-bhakti, execution of devotional service according to the regulative principles, and the other nine are varieties of prema-bhakti, ecstatic love of Godhead.
The nine varieties of prema-bhakti are rati, prema, sneha, māna, praṇaya, rāga, anurāga, bhāva and mahābhāva — attraction, love, affection, adverse feelings, intimacy, attachment, subattachment, ecstatic love and sublime ecstatic love. For the word sādhana-bhakti there is only one meaning, “the execution of devotional service according to regulative principles.”