Valmiki Ramayana Yuddha Kanda Sarga 77 Shloka 13
Original Shlokaस तुतेनप्रहारेणविचचालमहाकपिः ।।6.77.13।। परिघेणसमाधूतोयथाभूमिचलेऽचलः ।
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परिघेण by the iron club, समाधूतः with, सःमहाकपिः that great Vanara, तेन by that, प्रहारेण blow, भूमिचले mountain in earthquake, अचलःयथा not shake, विचचाल steady
The great Vanara did not move and remained steady like a mountain in an earthquake with the iron club touching him.