petition vs prayer

petition and prayer both are nouns.

Word	Noun	Adjective	Verb	Adverb
petition	Yes	No	Yes	No
prayer	Yes	No	No	No

As nouns, petition and prayer are synonyms defined as:

Other synonyms of petition include orison.

petition (noun)	prayer (noun)
a formal message requesting something that is submitted to an authority	the act of communicating with a deity (especially as a petition or in adoration or contrition or thanksgiving)
reverent petition to a deity	earnest or urgent request
	a fixed text used in praying
	reverent petition to a deity
	someone who prays to God

petition (verb)	prayer (verb)
write a petition for something to somebody; request formally and in writing