prayer in WordNet English dictionary

1. earnest or urgent request
   "an entreaty to stop the fighting"; "an appeal for help"; "an appeal to the public to keep calm"
   entreaty  prayer  appeal 
   
2. reverent petition to a deity
   prayer  petition  orison 
   
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 
   
4. a fixed text used in praying
   prayer 
   
5. someone who prays to God
   prayer  supplicant