Vesak
Concise Oxford English Dictionary © 2008 Oxford University Press:
Vesak /ˈvɛsak/ (also Wesak or Visākha)
▶noun the most important Buddhist festival, commemorating the birth, enlightenment, and death of the Buddha.
– origin Sinhalese vesak, via Pali from Sanskrit vaiśākha, denoting the month April–May.
'Vesak' also found in these Oxford entries:

