tree martin vs tree swallow

tree martin and tree swallow both are nouns.

Word	Noun	Adjective	Verb	Adverb
tree martin	Yes	No	No	No
tree swallow	Yes	No	No	No

As nouns, tree martin and tree swallow are synonyms defined as:

tree martin and tree swallow: of Australia and Polynesia; nests in tree cavities

Other synonyms of tree martin include Hirundo nigricans.

tree martin (noun)	tree swallow (noun)
of Australia and Polynesia; nests in tree cavities	of Australia and Polynesia; nests in tree cavities
	bluish-green-and-white North American swallow; nests in tree cavities