supplication

Short definition from Wiktionary

Noun

1. 1
   An act of supplicating; a humble request.
2. 2
   An act of supplicating; a humble request: du'a', minor or private prayer performed individually.
3. 3
   A prayer or entreaty to a god.
4. 4
   In Ancient Rome, a solemn service or day decreed for giving formal thanks to the gods for victory, etc.
5. 5
   The process by which a doctorate at Oxford university is officially requested after a thesis has been approved.