रावणस्य Ravana's, सुतः son, बली strong, तत् that, कर्म action, अमृष्यमाणः not tolerating, अमर्षणम् angry, तंसौमित्रिम् that Saumithri, दशभिः ten, बाणैः arrows, विव्याथ struck.

Indrajith, unable to tolerate the action of Saumithri, was angry and struck him with ten arrows.