blackcap vs pewit gull

blackcap and pewit gull both are nouns.

Word	Noun	Adjective	Verb	Adverb
blackcap	Yes	No	No	No
pewit gull	Yes	No	No	No

As nouns, blackcap and pewit gull are synonyms defined as:

Other synonyms of blackcap include Larus ridibundus, laughing gull, pewit.

blackcap (noun)	pewit gull (noun)
small brownish-grey warbler with a black crown	small black-headed European gull
chickadee having a dark crown
small black-headed European gull
raspberry native to eastern North America having black thimble-shaped fruit