house of prayer vs house of worship

house of prayer and house of worship both are nouns.

Word	Noun	Adjective	Verb	Adverb
house of prayer	Yes	No	No	No
house of worship	Yes	No	No	No

As nouns, house of prayer and house of worship are synonyms defined as:

house of prayer and house of worship: any building where congregations gather for prayer

Other synonyms of house of prayer include house of God, place of worship.

house of prayer (noun)	house of worship (noun)
any building where congregations gather for prayer	any building where congregations gather for prayer