from Latin Terra Australis (16c.), from australis "southern" + -ia. A hypothetical southern continent, known as terra australis incognita, had been proposed since 2c. Dutch explorers called the newfound continent New Holland; the current name was suggested 1814 by Matthew Flinders as an improvement over Terra Australis "as being more agreeable to the ear, and an assimilation to the name of the other great portions of the earth" ["Voyage to Terra Australis"]. In 1817 Gov. Lachlan Macquarie, having read Flinders' suggestion, began using it in official correspondence. The ultimate source is Latin auster "south wind," hence, "the south country" (see austral).
mid-15c., commoun welthe, "a community, whole body of people in a state," from common (adj.) + wealth (n.). Specifically "state with a republican or democratic form of government" from 1610s. From 1550s as "any body of persons united by some common interest." Applied specifically to the government of England in the period 1649-1660, and later to self-governing former colonies under the British crown (1917). In the U.S., it forms a part of the official name of Pennsylvania, Massachusetts, Virginia, Kentucky, and Puerto Rico but has no special significance.
marsupial mammal of Australia, 1798, from aboriginal Australian womback, wombar.
capital of Australia, 1826, from Aborigine nganbirra "meeting place."
"large, flightless bird of Australia and Papua," 1610s, via French or Dutch, from Malay (Austronesian) kasuari.