Canto 3 -
Araṇya-kāṇḍa
Chapter 48: Sītā-devī Condemns Rāvaṇa
Text 3.48.2

भ्राता वैश्रवणस्याहं सापत्न्यो वरवर्णिनि।
रावणो नाम भद्रं ते दशग्रीवः प्रतापवान्॥

bhrātā vaiśravaṇasyāhaṁ sāpatnyo vara-varṇini
rāvaṇo nāma bhadraṁ te daśagrīvaḥ pratāpavān

bhrātā = am a brother; vaiśravaṇasya = of Vaiśravaṇa; aham = I; sāpatnyaḥ = through a stepmother; vara-varṇini = O lady of excellent complexion; rāvaṇaḥ = Rāvaṇa; nāma = named; bhadram = auspiciousness; te = unto you; daśagrīvaḥ = I am ten-headed; pratāpavān = and powerful.

O lady of excellent complexion, auspiciousness unto you! I am a brother of Vaiśravaṇa through a stepmother. Named Rāvaṇa, I am ten-headed and powerful.

Rāvaṇa was the son of Vaiśravaṇa’s mother’s co-wife.

NOTE. Vaiśravaṇa is a name of Kuvera.