Valmiki Ramayana Sundara Kanda Sarga 42 Shloka 4
Original Shlokaस ता दृष्ट्वा महाबाहुर्महासत्त्वो महाबलः। चकार सुमहद्रूपं राक्षसीनां भयावहम्।।5.42.4।।
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महाबाहुः strong armed one, महासत्त्वः a great hero, महाबलः mighty, सः he, Hanuman, ताः the women, दृष्ट्वा seeing, राक्षसीनाम् for the ogresses, भयावहम् to create fear, सुमहत् very huge, रूपम् form, चकार assumed.
When the powerful, mighty and strongarmed Hanuman saw the ogresses he assumed a very huge form in order to strike terror in them.