bed and breakfast vs bed-and-breakfast

bed and breakfast and bed-and-breakfast both are nouns.

Word	Noun	Adjective	Verb	Adverb
bed and breakfast	Yes	No	No	No
bed-and-breakfast	Yes	No	No	No

As nouns, bed and breakfast and bed-and-breakfast are synonyms defined as:

bed and breakfast and bed-and-breakfast: an overnight boardinghouse with breakfast

bed and breakfast (noun)	bed-and-breakfast (noun)
an overnight boardinghouse with breakfast	an overnight boardinghouse with breakfast