lowan vs mound builder

lowan and mound builder both are nouns.

Word	Noun	Adjective	Verb	Adverb
lowan	Yes	No	No	No
mound builder	Yes	No	No	No

As nouns, mound builder is a hypernym of lowan; that is, mound builder is a word with a broader meaning than lowan:

lowan: Australian mound bird; incubates eggs naturally in sandy mounds
mound builder: large-footed short-winged birds of Australasia; build mounds of decaying vegetation to incubate eggs

Other hypernyms of lowan include megapode, mound-bird, mound bird, scrub fowl.

lowan (noun)	mound builder (noun)
Australian mound bird; incubates eggs naturally in sandy mounds	large-footed short-winged birds of Australasia; build mounds of decaying vegetation to incubate eggs