mew gull vs sea mew

mew gull and sea mew both are nouns.

Word	Noun	Adjective	Verb	Adverb
mew gull	Yes	No	No	No
sea mew	Yes	No	No	No

As nouns, mew gull and sea mew are synonyms defined as:

mew gull and sea mew: the common gull of Eurasia and northeastern North America

Other synonyms of mew gull include Larus canus, mew.

mew gull (noun)	sea mew (noun)
the common gull of Eurasia and northeastern North America	the common gull of Eurasia and northeastern North America