Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 170
Original Shlokaतं दृष्ट्वा वदनान्मुक्तं चन्द्रं राहुमुखादिव। अब्रवीत्सुरसा देवी स्वेन रूपेण वानरम्।।5.1.170।।
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राहुमुखात् from the mouth of Rahu, चन्द्रमिव like the Moon, वदनात् from the mouth, मुक्तम् released, तं him, वानरम् that vanara, दृष्ट्वा seeing, सुरसा देवी the divine Surasa, स्वेन in her true, रूपेण form, अब्रवीत् said.
Seeing Hanuman released out of her mouth like the Moon released from the mouth of Rahu, Surasa assumed her true form and said: