Synonyms for Prayer (same or very similar meaning)
WordNet sense 1 (someone who prays to God):
supplicant
WordNet sense 2 (reverent petition to a deity):
orison, petition
WordNet sense 3 (earnest or urgent request):
appeal, entreaty
WordNet sense 4 (the act of communicating with a deity (especially as a petition or in adoration or contrition or thanksgiving)):
supplication
From the ODE community, based on WordNet
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