prayer vs benediction

prayer and benediction both are nouns.

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

As nouns, benediction is a hyponym of prayer; that is, benediction is a word with a more specific, narrower meaning than prayer:

prayer: the act of communicating with a deity (especially as a petition or in adoration or contrition or thanksgiving)
benediction: the act of praying for divine protection

Other hyponyms of prayer include devotion, blessing.

As nouns, benediction is a hyponym of prayer; that is, benediction is a word with a more specific, narrower meaning than prayer:

prayer (noun)	benediction (noun)
the act of communicating with a deity (especially as a petition or in adoration or contrition or thanksgiving)	the act of praying for divine protection
earnest or urgent request	a ceremonial prayer invoking divine protection
a fixed text used in praying
reverent petition to a deity
someone who prays to God