Valmiki Ramayana Aranya Kanda Sarga 49 Shloka 1

प्रतापवाम् powerful, दशग्रीवः tenheaded Ravana, सीतायाः Sita's, वचनम् words, श्रुत्वा having heard, हस्ते by the palm, हस्तम् palm, समाहत्य striking, सुमहत् very great, वपुः body, चकार assumed.

On hearing the Sita's words, the powerful Ravana struck his palms one over the other and assumed a huge form (original figure). Ravana carries away Sita in his chariot-- she screams and wails aloud -- implores the animals, trees, mountains and rivers to tell Rama about her.