What is the meaning of Dunny?

Somewhat dun, dusky brownish.

Somewhat deaf, hard of hearing.

Slow to answer: stupid, unintelligent.

A dummy, an unintelligent person.

Alternative form of danna: shit.

An outhouse: an outbuilding used as a lavatory.

Any other place or fixture used for urination and defecation: a latrine; a lavatory; a toilet.

A passageway, particularly those connecting an outhouse to the main building.

A cellar, basement, or underground passage.

Source: wiktionary.org