A type of Parīṣaha (hardships);
the pain due to hot climate, which is to be endured with equanimity by the ascetic (Muni).
usiṇapariyāveṇaṃ paridāheṇa tajjie. ghiṃsu vā pariyāveṇaṃ sāyaṃ no paridevae...
uṇhāhitatte mehāvī siṇāṇaṃ no vi patthae. gāyaṃ no parisiṃcejjā na vīejjā ya appayaṃ...
(U 2.8,9)