The term 'Down Under Dweller' refers to a person who lives in Australia, which is often referred to as 'Down Under' due to its location in the Southern Hemisphere. The two crossword solutions for this term are 'KOALA' and 'Aussie'. KOALA is a five-letter word that refers to a species of marsupial native to Australia, while Aussie is a six-letter word that is a colloquial term for an Australian person or citizen.