"native or resident of Indiana," by c. 1830, American English, of unknown origin; newspapers in the 1830s published fanciful explanations, some still repeated, "none authenticated by evidence" [Century Dictionary]. Said to have been first printed Jan. 1, 1833, in the "Indianapolis Journal," in a poem, "The Hoosiers Nest," by John Finely, which poem was said to have been written in 1830 ["The Word Hoosier," Indiana Historical Society Publications, vol. iv, no. 2, 1907], and to have been in oral use from late 1820s. Seemingly it originated among Ohio River boatmen; perhaps related to English dialectal (Cumberland) hoozer, used of anything unusually large [Barnhart]. For other theories, see the historical society article. The word also has been used generally for "country bumpkin."
1926 in the U.S. geographical sense, from earlier Midwestern (1889) in reference to a group of states originally listed as West Virginia, Kentucky, Tennessee, Missouri, Kansas, and Arkansas; it now generally refers to states somewhat north and west of these (according to the U.S. Census Bureau, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin). Related: Midwesterner.
Errata — Page 263, line 9 from bottom, for 'orthodoxy' read orthopraxy. This is a new coin from the mint of Dr. [Andrew] Wylie [of Bloomington College, Indiana], at least I have not before noticed it. Its etymology places it in a just contrast with orthodoxy: for if that consecrated word indicates thinking right, orthopraxy will legitimately import doing right, and hence, as Mr. Wylie says, orthopraxy in the last dread day will pass the divine ordeal incomparably better than orthodoxy. O! that a zeal for orthopraxy would transcend the zeal for orthodoxy! ["The Millennial Harbinger," vol. iv, no. 8, Bethany, Virginia, August 1840]
also north-west, Old English norþwest (adv.) "to a point or in a direction between north and west;" from north + west. As a noun, "region or locality lying in the northwest of a country," and adjective from late 14c.
In U.S. geography it was at first, the territory that later became Ohio, Indiana, Illinois, Wisconsin, Michigan and northeastern Minnesota (1787); after about 1853 the term was applied to the unorganized territory north of Nebraska, west of Minnesota, and east of the Rockies. Pacific Northwest, describing Oregon and Washington, is by 1874. Related: Northwestern; northwesterly; northwestward (late 14c.).
Northwest Passage as the name of an at-first hypothetical sea route from the Atlantic to the Pacific by the northern coasts of North America, first attested c. 1600. The Northwest Ordinance (1787) was an act of Congress to organize the territory beyond the Appalachian Mountains between the Great Lakes and the Ohio River.
1737, "a medicine which excites vomiting;" by 1938 as "material thrown up in vomiting," from puke (v.). U.S. colloquial meaning "native of Missouri" (1835) might be a different word, of unknown origin.
It is well known, that the inhabitants of the several western States are called by certain nicknames. Those of Michigan are called wolverines; of Indiana, hooshers; of Illinois, suckers; of Ohio, buckeyes; of Kentucky, corn-crackers; of Missouri pukes, &c. To call a person by his right nickname, is always taken in good part, and gives no offence; but nothing is more offensive than to mis-nickname—that is, were you to call a hoosher a wolverine, his blood would be up in a moment, and he would immediately show fight. [A.A. Parker, "Trip to the West and Texas," Concord, N.H., 1835]
Bartlett (1859) has "A nickname for a native of Missouri" as the second sense of puke (n.), the first being "A mean, contemptible fellow." The association of the state nickname with the "vomit" word is from at least 1858, and folk etymology talks of the old state literally vomiting forth immigrants to California.