CC Madhya 8.160

premera parama-sāra ‘mahābhāva’ jāni
sei mahābhāva-rūpā rādhā-ṭhākurāṇī
Word for word: 
premera — of love of Godhead; parama-sāra — the essential part; mahā-bhāva — the transcendental ecstasy of the name mahābhāva; jāni — we know; sei — that; mahā-bhāva-rūpā — the personification of the mahābhāva transcendental ecstasy; rādhā-ṭhākurāṇī — Śrīmatī Rādhārāṇī.
Translation: 
“The essential part of love of Godhead is called mahābhāva, transcendental ecstasy, and that ecstasy is represented by Śrīmatī Rādhārāṇī.