upa-drava m. that which attacks or occurs suddenly, any grievous accident, misfortune, calamity, mischief, national distress (such as famine, plague, oppression, eclipse, &c.)

• national commotion, rebellion

• violence, outrage MBh. R. Śak. VarBṛS. &c. 

• a supervenient disease or one brought on whilst a person labours under another Suśr

• the fourth of the five parts of a Sāman stanza ṢaḍvBr. Comm. on TĀr. &c