Welsh rabbit vs rarebit

Welsh rabbit and rarebit both are nouns.

Word	Noun	Adjective	Verb	Adverb
Welsh rabbit	Yes	No	No	No
rarebit	Yes	No	No	No

As nouns, Welsh rabbit and rarebit are synonyms defined as:

Welsh rabbit and rarebit: cheese melted with ale or beer served over toast

Other synonyms of Welsh rabbit include Welsh rarebit.

Welsh rabbit (noun)	rarebit (noun)
cheese melted with ale or beer served over toast	cheese melted with ale or beer served over toast