supplication in WordNet English dictionary

1. a prayer asking God's help as part of a religious service
   invocation  supplication 
   
2. a humble request for help from someone in authority
   supplication  plea 
   
3. the act of communicating with a deity (especially as a petition or in adoration or contrition or thanksgiving)
   "the priest sank to his knees in prayer"
   prayer  supplication