Valmiki Ramayana Bala Kanda Sarga 75 Shloka 16
Original Shlokaविरोधे च महद्युद्धमभवद्रोमहर्षणम् । शितिकण्ठस्य विष्णोश्च परस्परजिगीषुणो:।।1.75.16।।
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विरोधे in that fight, परस्परजिगीषिणो: each desirous of victory over the other, शितिकण्ठस्य Siva's, विष्णोश्च Visnu's, रोमहर्षणम् causing one's hair to stand on its end, महत् great, युद्धम् battle, अभवत् took place.
In that thrilling fight between Siva and Visnu, each desirous of victory over the other, a ferocious battle took place causing one's hair to stand on end.