What did Australia used to be called what?

It used to be called New Holland

Thailand used to be called Siam, Ethiopia was once known as Abyssinia, and Australia was initially christened New Hollandwhen Dutch navigators “discovered” it in the 17th century. The land Down Under received its current English name courtesy of British explorer Matthew Flinders, the first to circumnavigate the continent, who made a hand-drawn map a year later in 1804, referring to it as Australia. Britain formally adopted that name for the country in 1824, and by the end of the 1820s it was widely used.  

For centuries, European cartographers had referred to the land as Terra Australis Incognita (Unknown South Land). They believed there was a massive, uncharted landmass somewhere in the Southern Hemisphere, even if they didn’t yet know the details. Of course, Australia’s Indigenous peoples have inhabited the continent for more than 50,000 years — or by their own account, since the beginning of time.

Despite being thousands of miles away, Australia is New Zealand’s closest neighbor and unofficial “big brother.” What’s more, they’re as linked by history and etymology as they are by geography: Dutch navigator Abel Janszoon Tasman first sighted New Zealand's South Island in 1642, and cartographers named it in honor of the Dutch maritime province Zeeland. The larger of New Zealand's two main islands, it's also known as Te Waipounamu, while the North Island carries the Māori name of Te Ika-a-Māui.