moor-bird vs red grouse

moor-bird and red grouse both are nouns.

Word	Noun	Adjective	Verb	Adverb
moor-bird	Yes	No	No	No
red grouse	Yes	No	No	No

As nouns, moor-bird and red grouse are synonyms defined as:

moor-bird and red grouse: reddish-brown grouse of upland moors of Great Britain

Other synonyms of moor-bird include Lagopus scoticus, moorbird, moorfowl, moorgame.

moor-bird (noun)	red grouse (noun)
reddish-brown grouse of upland moors of Great Britain	reddish-brown grouse of upland moors of Great Britain