तस्मिन् in that time, समरे in the battle, रावणः Ravana's, शरैः arrows, महाभ्राणि huge clouds, मारुतःइव like wind, प्लवङ्गमानाम् leaping, अनीकानि many, विधमन् dissipate, संययौ went in the battlefield

At that time, driven by Ravana's arrows, the Vanaras fled from the battlefield just like huge clouds are dissipated by wind.