A 1921 headline from The Spartanburg Herald-Journal in South Carolina reads "The Whole Six Yards of It."
The whole nine yards or full nine yards is a colloquial American phrase meaning "everything, the whole lot" or, when used as an adjective, "all the way," as in, "The Army came out and gave us the whole nine yards on how they use space systems." Its origin is unknown and has been described as "the most prominent etymological riddle of our time."
The earliest known example of this phrase is from 1907 in southern Indiana. It is related to the expression "the whole six yards," used around the same time in Kentucky and South Carolina. Both phrases are variations on the whole ball of wax, first recorded in the 1880s. They are part of a family of expressions in which an odd-sounding item, such as enchilada,shooting match, shebang or hog, is substituted for "ball of wax." The choice of the number nine may be related to the expression "to the nines" (to perfection).[nb 1]
The phrase was introduced to a national audience by Elaine Shepard in the Vietnam War novel The Doom Pussy (1967). Use of the phrase became widespread in the 1980s and 1990s. Much of the interest in the phrase's etymology can be attributed to New York Times language columnist William Safire, who wrote extensively on this question.
The earliest known use of the phrase is from The Mitchell Commercial, a newspaper in the small town of Mitchell, Indiana, in their 2 May 1907 edition:
This afternoon at 2:30 will be called one of the baseball games that will be worth going a long way to see. The regular nine is going to play the business men as many innings as they can stand, but we can not promise the full nine yards.
The phrase was used three more times in the Mitchell Commercial over the next seven years, in the forms "give him the whole nine yards" (i.e., tell someone a big story), "take the whole nine yards" (i.e., take everything), and "settled the whole nine yards" (i.e., resolved everything).
In other uses from this time period, the phrase was given as "the whole six yards." In 1912, a local newspaper in Kentucky asked readers to, "Just wait boys until the fix gets to a fever heat and they will tell the whole six yards." The six-yard form of the phrase also appears in a 1921 headline in a local South Carolina paper.
The phrase is not known to have been used in writing thereafter until a 1956 issue of Kentucky Happy Hunting Ground, where it appears in an article on fishing. After describing the contests and prizes, the author writes, "So that's the whole nine-yards." It appeared in an article on hunting the following year, this time unhyphenated.
The phrase at this point was still rare. There is strong circumstantial evidence it was not in general use in 1961, as Ralph Boston set a world record for the long jump that year at 27 feet, or nine yards, but no news report has been found that made any reference to the term, suggesting that journalists were unaware of it or did not regard it as common enough to use as a pun.
In a short story published in 1962, the phrase is attributed to "a brush salesman." A letter published in an auto magazine later that year describes a certain new car as containing "all nine yards of goodies". In 1964, several newspapers published a syndicated story which explained that, "Give 'em the whole nine yards" was NASA talk for an item-by-item report. This early usage can be read as suggesting length, but can also be read as suggesting detailed completeness.
Two 1965 newspaper articles quote U.S. military personnel serving in Vietnam using the phrase. The phrase was explained as something "teenagers say" in a military-oriented magazine in 1965. Citations from 1966 show the phrase was used by a former U.S. Army airman, and also in a publication for military test pilots. It is also recorded in two contemporary novels concerning the U.S. Air Force in Vietnam, Carl Krueger's Wings of a Tiger (1966), and Elaine Shepard's The Doom Pussy (1967).
Several key discoveries in further antedating the phrase were made by Bonnie Taylor-Blake, a neuroscience researcher at the University of North Carolina at Chapel Hill and an amateur member of the American Dialect Society, an association of professional and amateur linguists whose mailing list often serves as a forum for word and phrase discoveries. In 2012, Taylor-Blake discovered the 1956 and 1957 uses in Kentucky Happy Hunting Ground, and later that year she and Fred R. Shapiro found the "whole six yards" examples from the 1912 - 1921 period, which received substantial publicity. In 2013, Taylor-Blake posted her discovery of the Mitchell Commercial uses from the 1907 - 1914 period.
There is still no consensus on the origin, though many early published quotations are now available for study. A vast number of explanations for this phrase have been suggested; many of these are no longer viable in light of what is now known about the phrase's history.
Perhaps the most commonly offered explanation is that World War II (1939–1945) aircraft machine gun belts were nine yards long. There are many versions of this explanation with variations regarding type of plane, nationality of gunner, and geographic area. This theory is no longer considered viable, since the phrase predates World War II. However an alternative weapon is the ammunition belt for the British Vickers machine gun, invented and adopted by the British Army before the first World War (1914 - 1918)
Another common explanation is that "nine yards" is a cubic measure and refers to the volume of a concrete mixer. This theory, too, is inconsistent with the phrase's history.
One proposed origin involves the world of full-rigged sailing ships, in which yard is used not as a measure of length or size, but as the name of each horizontal spar on which a sail is hung. All square-rigged sails unfurled, with 3 yards on each of 3 masts, could then be described as "the whole nine yards,"  but again no actual documentation has been uncovered to support this explanation.
Bonnie Taylor-Blake, noting that several early examples are in the form "give" or "tell" the whole nine (or six) yards, has suggested that the idiom likely relied on "yards" as "lengthy or thorough presentation [of news, anecdotes, play-by-play, etc.]"
^The phrase "to the nines" is first recorded in 1687. In early usage, it suggested that a work met the standards of the nine Muses of Greek mythology. Nine is considered a perfect number in numerology as it is three squared. Note that the phrase "cloud seven" was inflated to "cloud nine" by the same process. See The Phrase Finder and Random House Historical Dictionary of American Slang. Dressing "To the Nines" could also refer to the fact that in French "neuf" means both 9 and New ("Mes souliers sont neuf" = "My shoes are new"). So, "dressing to the nines" would mean dressing in a new outfit ("neuf").
^Whole, adj., n., and adv., C2, compound whole nine yards, Oxford English Dictionary (OED Online version Mar. 2013) (citing 1983 Aviation Week 7 Mar. 46/2).
^ abShepard, Elaine, The Doom Pussy, Trident Press, (1967), p. 54; "Slipping out of the knot [marriage] was expensive but Smash was eventually able to untangle what he called 'the whole nine yards.'" The phrase appears several times in the book, always as the pet usage of Major "Smash" Crandell, a U.S. Air Force navigator. At one point, Smash refers to, "the ninth yard" (finishing touch).
^"Baseball," Mitchell (Ind.) Commercial p. 2,col. 3 (May 2, 1907).
^Mitchell (Ind.) Commercial, p. 3, col. 5 (June 4, 1908).
^"Third Term Superstition," Mitchell (Ind.) Commercial p. 2, col. 2 (Oct. 10, 1912).
^"Story of a Green Basket," Mitchell (Ind.) Commercial p. 1, col. 5 (Nov. 26, 1914).
^ abcdefghiJennifer Schuessler (December 26, 2012). "The Whole Nine Yards About a Phrase’s Origin". New York Times. Retrieved 2012-12-29. "Then, in August, Bonnie Taylor-Blake, a neuroscience researcher in North Carolina who had been searching for variants of the phrase via Google News Archive and Google Books for five years, posted a message on the e-mail list of the American Dialect Society noting a 1956 occurrence in an outdoors magazine called Kentucky Happy Hunting Ground, followed in September by a more startling twist: a 1921 headline from The Spartanburg Herald-Journal in South Carolina reading "The Whole Six Yards of It." ... The recent discovery of several instances of "the whole six yards" in newspapers from the 1910s — four decades before the earliest known references to "the whole nine yards" — opens a new window onto "the most prominent etymological riddle of our time," said Fred Shapiro, a librarian at Yale Law School who announced the findings in next month’s issue of The Yale Alumni Magazine. ..."
^Rhody, Ron (July 1956). "Kentucky Afield Fishing Derbies Are Underway". Kentucky Happy Hunting Ground12 (4): 18.
^See also "Plugs and Bugs" by Ferd Holtmann, Kentucky Happy Hunting Ground, Vol. 18. No. 2, March, 1962, page 6. "Most anglers will tell you he has six or seven baits he uses more than all the others combined, yet he would be lost without the entire nine yards. It might be said there's a feeling of security involved in carrying the whole load on every outing."
^Wegner, Robert E., "Man on the Thresh-Hold," Michigan's Voices, Fall 1962. "...the consequence of house, home, kids, respectability, status as a college professor and the whole nine yards, as a brush salesman who came by the house was fond of saying, the whole damn nine yards."
^Linster, Gale F., "Constructive Criticism," Car Life Vol. 9, Issue 11 (December 1962), p. 2. "Your staff of testers cannot fairly and equitably appraise the Chevrolet Impala sedan, with all nine yards of goodies, against the Plymouth Savoy which has straight shift and none of the mechanical conveniences which are quite common now."
^Campbell, Frank D., Jr. Lt. Col, Daily Facts, (Redlands, CA), April 7, 1965, p. 6. "We got the whole nine yards, including a side trip to Panama for jungle survival." (Quote attributed to Maj Clyde B. Williams.) Burris, Keith, "'Burners' Are Not Informed", Deseret News, 28 December 1965, (Salt Lake City, UT), p. A11, col. 1; "Capt. Greer was on alert the night of the big Red raid on Piel Me. He said the Cong troops were extremely well outfitted with steel helmets, boots -- 'the whole nine yards of uniform.'"
^Andrus, Col. Burton C. Jr, Assembly [magazine], Association of Graduates, United States Military Academy, v. 23 n. 3 col. 3, Fall 1965, p. 53 (55 of 100 in pdf). "We have 60 of the 120 rooms reserved so far--why not take over "the whole 9 yards" as the teenagers say?"
^Guthrie, James M., "Sesquicentennial Scrapbook", National Road Traveler, [Cambridge City, Indiana], 30 June 1966, p. 3; "If you like "The Old Swimmin' Hole," "Raggedy Man" and "When the Frost is on the Pumpkin" you'll like this one. And J.W. Riley is only a small contributor. (But Riley would have loved the whole nine yards)." For Guthrie's biographical information, see here.
^Technical Review, The Society of Experimental Test Pilots, Vol. 8, No. 2, p. 176 (September 1966) "Then two-engines, two pilots, and the rest, the nine yards of things that we have really all been aware of for a long time and should pay a lot more attention to."
^Krueger, Carl, Wings of the Tiger: A novel (1966); "'Okay, Tiger,' it said. 'Give 'em the whole nine yards. Now!'" [An instruction to fire at the enemy], p. 39. "We'll go over it after de-briefing. Get me a list of all pilots and planes available. Everything. The whole nine yards." p. 57.