Aussie vs Abo

Aussie and Abo both are nouns.

Word	Noun	Adjective	Verb	Adverb
Aussie	Yes	No	No	No
Abo	Yes	No	No	No

As nouns, Abo is a hyponym of Aussie; that is, Abo is a word with a more specific, narrower meaning than Aussie:

Aussie: a native or inhabitant of Australia
Abo: a dark-skinned member of a race of people living in Australia when Europeans arrived

Other hyponyms of Aussie include Aborigine, Australian Aborigine, native Australian.

Aussie (noun)	Abo (noun)
a native or inhabitant of Australia	a dark-skinned member of a race of people living in Australia when Europeans arrived