Possibly one of the most misattributed phrases in English, “the whole nine yards,” which means “to the fullest extent” or “all the way through,” has many purported origins, and which one you pick as correct seems to depend on where you’ve come from.
The Textiles Theory
Fabric was commonly measured in yards, and some theorists posited that the “whole nine yards” refers to the amount of fabric that’s required to make—depending on who you talk to—a man’s three-piece suit, Scottish kilts, bridal veils or a variety of other common clothing items.
The Concrete Truck Theory
Favored by famed creative curmudgeon William Safire, this explanation deals with the construction industry. Safire writes:
Richard Carlsen of Manchester, Conn., caught my plea on WPOP radio and wrote: ”Next time you pass by a construction site where they are using a large cement mixer – one of those trucks with a revolving cylinder on the back out of which cement pours down a chute – ask them if it’s going to take ‘the whole nine yards.’ You see, one of those large, elephantlike conveyances will hold nine cubic yards of cement. Hence, any job that requires all the truck has will take ‘the whole nine yards.’ ” Mr. Carlsen adds: ”Now all I have to do is find out where to mail this. I think they said The New York Times.”
The Ball of Wax Theory
The “whole ball of wax,” the “whole shootin’ match” and other similarly structured phrases were linked as a common set of variations on the same root phrase, which has its origins in the rural Southern United States. These phrases all deserve their own article, but their intent is roughly equivalent to the whole nine yards, and communicate a thoroughness of intent in the same spirit as our target phrase.
The .50-Caliber Theory
Perhaps the most popular theory—and one with the least amount of actual evidence—is the .50-caliber theory, which goes something like this: The ammunition belts used to feed the M2 Browning machine gun popular with ground combat soldiers during World War II were supposedly 27 feet (nine yards) long, so giving them “the whole nine yards” meant unloading every round in the belt at a target.
This theory is popular because it fits the current common usage of the phrase—a machine gun is nothing if not thorough in its purpose—and romantic, in a way (what’s more boring than textiles, besides a ball of wax?). New York Times commenter Ray from Seattle explains it thusly:
I’m old enough to remember former W.W. II fighter pilots using the nine-yard phrase in the euphemistic context of “… really gave [them] hell.” ( A ‘bad’ word, spoken in the polite society of the early ’50s.) Continuously firing the entirety of twenty-seven feet of .50 cal ammunition (per machine gun) – delivered with passion – reasonably meets that test.
The .50 cal account was the common/accepted association when I was an Army Aviator, toward the end of the Viet Nam War. More specifically, the term was referenced to the ‘standard’ .50 cal machine gun capacity aboard a P-51, Mustang. …
In any case, that’s my conviction – and I’m sticking to it!
Except there’s no evidence that these ammo belts were actually 27 feet (nine yards) long, and as snopes.com points out, ammunition was (and still is) commonly referred to by its caliber, not by the length of whatever’s holding it.
For more on the “whole nine yards” debate, check out the full New York Times article—the actual article says very little, but link is worth clicking for the comments (from which I’ve attributed several succinct iterations of these theories).