shaft louse vs chicken louse

shaft louse and chicken louse both are nouns.

Word	Noun	Adjective	Verb	Adverb
shaft louse	Yes	No	No	No
chicken louse	Yes	No	No	No

As nouns, shaft louse and chicken louse are synonyms defined as:

Other synonyms of shaft louse include Menopon gallinae, Menopon palladum.

shaft louse (noun)	chicken louse (noun)
a louse parasitic on poultry	a louse parasitic on poultry