Alain, as you have done me so much service with your etymologies, I simply must do you one ;)
Nitty-gritty comes by way of African-American culture, southern and south-western African-American culture to be exact,
and the word was attested orally as early as the 1920s. Let me quote from a paper, The Real
Nitty Gritty by a W. R. Higginbotham and J.A., from whence nearly all my information comes:
The earliest uses of nitty-gritty are in registers characteristic of black America, and
they continue: jazz music and musicians (1961, 1963a, 1965, 1966a, 1969c, 1971c), civil rights
and black power (1963b, c, 1966d,1967c, d, 1968a, b, 1970d), and as an ingredient in that elusive
quality that pervades and identifies all things black-soul (1966a, b, 1967b, 1969b, d).
The citations are left in without a bibliography, so that you may see the date of first attestation.
From African-American culture, it then apparently passed into the lingo of college students at about
the time of the 1960s, by way of popular music, and was probably helped in its adoption by the
general countercultural mood of that era. (Remember this was the era of "the [Civil Rights]
struggle"; knowing the obscure argot of an oppressed people would have likely seemed appealingly
dangerous and sexy to college students.) From there, it spread into the general culture via writers and
high-circulation periodicals, such as The New York Times and Newsweek. One song written in
1963, by a Licoln Chase, titled simply The Nitty Gritty, appears to have been especially
influential in the uptake of the word. I reproduce the first few lines:
Some folks know about it, some don't.
Some will learn to shout it, some won't.
But soon or later, baby, here's a ditty,
Say you're gonna have to get right down to the real NITTY GRITTY.
Let's get right down to the real NITTY GRITTY,
now one, two NITTY GRITTY,
now yeah, boom NITTY GRITTY,
now ooooh-iee. Right down to the real NITTY GRITTY!
Oooh-oooh! Oooh-oooh!
More from the paper:
The word seems to have been first used as a noun (1961-63); and, although it passed
easily and early in its recorded history into adjectival use (1964b, 1966d, 1967c, d, 1968a,
1969e, f, 1971a, 1973c), it has remained predominantly a noun. Indeed, by far the most
frequent collocation of the term is some form of the expression get right down to the real
nitty-gritty, which, in one variant or another, accounts for about half of the total
number of citations. That phrase also accounts for the earliest uses.
But you're probably wondering how this phrasing get down to the nitty gritty was coined
originally. Well, here's where it gets disgusting. In fairness, there is actually some disagreement
about the following explanation in the paper -- Higginbotham promotes the idea in the beginning,
while J.A. argues against it -- but it is easily the most intriguing one I found therein, so I must
reproduce it. Apparently, the "nitty" in nitty gritty refers to actual nits, as in lice, and the
gritty was initially a reference to ground hominy, and then
became a reference the grinding action one uses to reproduce the staple. Of course, that in turn was easily
sexualized in meaning so that gritty also came to describe the grinding action of raw, bestial
intercourse. Thus, getting down to the nitty-gritty means getting down so deep in a woman that
one feels everything of her movements, and I do mean everything. The paper gives this joke to illustrate:
Both black men at Amarillo insisted to me that nitty gritty sprang from what they described
as an old, black, nearly pointless joke that goes:
A man having intercourse with a smart-alecky girl took an unusually long stroke, making her jump.
Thinking he had impressed her, he asked, "Did I hit it, honey?" "Yeah," she said. "Wrong
way. You hit the real nitty gritty."
Wow! Amazing language, our English.
Wireless World
Here's the start of the story Callithumpian found in Wireless World (possibly volume 88, 1982):
In your February issue, Pat Hawker mentions "SNAFU" as a coinage of War II. I think he and your readers may be interested to know its pre-war origin.
During the said war it was my pleasure to work for a time with two clever and humorous American Western Electric telephone engineers, and they told me that their pre-war jobs had been to go to telephone exchanges where there was trouble and rectify it. Upon arrival at the site an engineer would make a brief estimate of how serious was the trouble, establish a telephone link to his headquarters and send back a code word. His home base would therefore know he had arrived where the problems were, have a rough idea of how long it would take to clear them and have a telephone number where he could be contacted if need be. There were three code words: SNAFU - Situation normal, all fouled up" (or words to that effect); TARFU - "Things are really fouled up"; and FUBAR - "Fouled up beyond any repair". The latter would be sent if, for instance, a telephone exchange had been seriously damaged by fire or flood, while SNAFU would be used for a situation where cables or machinery had been damaged but where repairs or replacement would be ...
OED
Back to SNAFU. The OED says it's also originally US military slang, with the first citation from a September 1941 edition of American Notes & Queries, apparently in reply to a May 1941 article:
<< ARMY AIR SLANG (1:22 May '41)
The influence of air slang seems to have had no effect on army lingo here. There is very little, in all, that could be called really new: and most of it is unprintable. But if AN&Q would like these three — just for the record — here they are:
latrine-o-gram — baseless rumor (the latrine is the source of many a baseless rumor!)
snafu — situation normal
susfu — situation unchanged
Private "W"
Camp Forrest, Tenn.
This suggests SNAFU entered army slang from air slang.
Don Taylor
Roaring Fish found another etymology of SNAFU from Don Taylor (wayback). Taylor says in April or May of 1941 (before Pearl Harbor) during radio network training at Camp San Luis Obispo, California, it came from a mechanical coding device that scrambled messages into five letter code groups. He and John Paup entertained themselves by forming initialisms from the codes.
Taylor's son Greg (wayback) writes:
One day, as he recalls, he received a code group S.N.A.F.U. from
Johnny Paup.
"It was instantaneous, inevitable, and there was no question," the
words came to him; "SITUATION NORMAL, ALL F - - - - D UP! To Taylor
and other enlisted types, this perfectly described the military
growing pains before and just after Pearl Harbor.
Eventually S.N.A.F.U. spread like V.D. in an off base W - - - E house.
It went everywhere there was radio communication. The Pentagon literally survived on various levels of "SNAFU" until Warner Brothers picked up on it for their training film star!
Don continues:
As to how it spread, there is no way of knowing for certain. I think initially it got spread all over the 40th Infantry Division. At that point in time people were being sent to training schools such as Fort Monmouth, N.J., & Fort Benning Georgia. People from other divisions would be attending such schools and would take "SNAFU" back to their outfits when their training was completed. We also had people that were already proficient in certain jobs and they were sent in small groups to become the nucleus for new Divisions. There were also a number of individuals that were sent to Officer Candidate schools.
OED antedatings
Taylor's story is discussed on the Snopes forums:
Fred Shapiro has provided evidence that "snafu" was in use at Camp Joseph T. Robinson (North Little Rock, Arkansas) in late July,
1941, a sighting that slightly antedates that which the OED provides.
(I've also found two instances of "snafu" in use in early August,
1941, also with regard to khaki field hats. As with Shapiro's July
find, soldiers from Kansas reported using the term at Camp Robinson.
There's no indication in these August newspaper articles that "snafu"
is an acronym, but a private does describe the new hats as "horrible,"
so one might assume that "snafu" generally referred to things and
situations "all fucked up.")
I guess a question, then, is whether there's enough time for an
acronym said to have been coined in San Luis Obispo in April/May 1941
to have made it to North Little Rock by late July. I think it's at
least possible, given that the explanation in the link in the OP
offers an origin in radio transmission and mentions that,
Quote: As to how it spread, there is no way of knowing for certain. I think initially it got spread all over the 40th Infantry Division. At that point in time people were being sent to training schools such as Fort Monmouth, N.J., & Fort Benning Georgia. People from other divisions would be attending such schools and would take "SNAFU" back to their outfits when their training was completed. We also had people that were already proficient in certain jobs and they were sent in small groups to become the nucleus for new Divisions. There were also a number of individuals that were sent to Officer Candidate schools.
Note that Shapiro's July find mentions that "[t]he sergeant went on to
explain that 'snafu' was a term the 35th division outfits that went on
maneuvers over in Tennessee last month [June] imported to Camp
Robinson." It's difficult to know whether the Tennessee usage referred
specifically to hats or whether this reflected a general usage of
"snafu" with its implication that things were "fucked up."
Shapiro's sergeant says the name first applied to khaki hats, and suggests the name came first and then "somebody decided it was a bunch of letters that stood for words". These hats references are interesting, and deserve more attention -- did why exactly was snafu used for hats in the first place?
There's also Tennessee again, where Private "W" wrote from in September 1941 (OED).
Barry Popik found this in the San Francisco Chronicle, 15 June 1941, pg. 5, col. 4:
Slanguage
Army Camps
Developing a
Dictionary
(...)
"Snafu" means "situation normal, all fuddled up."
(...)
"Red Lead" is tomatoes, tomato sauce or ketchup.
Cream and sugar or salt and pepper are "sidearms." Salt, alone, is
"sea-dust."
(...)
Spinach is "seaweed."
Bonnie Taylor-Blake adds:
From Howard Needham's "Slanguage: Army Camps Developing a
Dictionary," The San Francisco Chronicle, 15 June 1941, p. 5.
Needham, a staff writer for the Chronicle, filed his report from
Hunter Liggett Reservation, southern Monterey County, California the
previous day. He attributed a crop of expressions new to Hunter
Liggett to some 35,000 troops who had arrived from Fort Lewis,
Washington.
Acronyms in general
Back to the Wireless World story. The story tells of two telephone engineers who used SNAFU, TARFU and FUBAR as code words in their pre-war jobs at Western Electric (founded 1872, defunct 1995).
It's possible, but seems unlikely partly because there's no written evidence that these were used before World War II.
"TARFU" was our embellishment on "snafu." Snafu, already in use all over the US and not only in the military, meant "Situation normal, all fucked up." You were supposed to say this with a resigned shrug of the shoulders, indicating that the submoronic people and junky devices you had to deal with would naturally fail. We in troop carrier, responsible as we were for immensely delicate and complex machinery and saddled with impossibly ambitious flying assignments, had to go beyond snafu; so we used "Things Are Really Fucked Up!"
- And finally, apart from a few exceptions such as POTUS, "acronyms didn't become a common method of word formation in English until World War II", according to the Online Etymology Dictionary.
Best Answer
Coverage of 'nitty-gritty' in slang dictionaries
J.L. Lighter, Random House Historical Dictionary of American Slang (1997) has entries for nitty-gritty as a noun and for nitty-gritty as an adjective, the former usage evidently being somewhat older than the latter:
Jonathon Green, Cassell's Dictionary of Slang, second edition (2005) takes a similar view of the term's origin, although perhaps a bit more guardedly:
As Lighter indicates, the term appears in the supplementary section of Harold Wentworth & Stuart Flexner, Dictionary of American Slang, supplemented edition (1967). Here is the full entry for the expression in that dictionary:
Robert Chapman, New Dictionary of American Slang, (1986) puts forward a different origin theory for the term:
Robert Hendrickson, Encyclopedia of Word and Phrase Origins, second edition (1997) endorses Chapman's theory about the origin of the expression:
In contrast, none of the three general African American dictionaries I consulted offers an origin story for nitty-gritty. The earliest of the three, Clarence Major, Dictionary of Afro-American Slang 1970) has this brief entry:
Major's much longer and much better documented Juba to Jive: A Dictionary of African-American Slang (1994) unfortunately doesn't add much to the 1970 volume's treatment. It repeats the earlier definition, adding only that the period of popular Black use of the expression was the "1960s–1970s." It also includes a couple of citations, but these are disappointing. One is to the edition of Wentworth & Flexner noted earlier in this answer, and the other is to page 188 of Robert Gold, A Jazz Lexicon (1964); unfortunately Gold does not have an entry for nitty-gritty, and there is not even a passing mention of the term on page 188.
The coverage of nitty-gritty in Geneva Smitherman, Black Talk: Words and Phrases from the Hood to the Amen Corner (1994) is likewise perfunctory:
Tom Dalzell & Terry Victor, The New Partridge Dictionary of Slang and Unconventional English (2006) address the etymological question somewhat combatively:
Early 1950s instances of 'nitty gritty' in the wild
Although Dalzell & Victor gives 1956 as a first documented occurrence date, the first published instance it cites is from 1964. But Greybeard's answer cites an instance of the expression from 1940 in the Pittsburgh [Pennsylvania] Courier—a historically Black periodical, according to the Wikipedia article about it. That instance is much earlier than any I could find in various online database searches.
The four earliest instances I could find were from 1952 and 1953, from two repeat authors. From Luke Roberts, Harlem Model (1952) [combined snippets]:
From A.S. "Doc" Young, "Inside Sports," in Jet magazine (October 2, 1952):
From Luke Roberts, Harlem Doctor (1953) [combined snippets]:
And from A.S. "Doc" Young, "Inside Sports" in Jet magazine (February 26, 1953):
Luke Roberts was (the pseudonym of) a novelist who produced potboiler/torrid romance titles. A sampling of the original paperback covers for his novels is posted at this Facebook site. Doc Young was a longtime sportswriter at various newspapers and magazines. Between them, they may have done more than any other two ink-stained wretches on the planet to popularize nitty-gritty in the early 1950s.
About that 'slave ship debris' explanation ...
Dalzell & Victor's capsule debunking of the "slave ship debris" theory of the phrase's origin raises a couple of obvious questions: where and when did that "debris" theory arise?
According to Dalzell & Victor, it occurred "in the early 2000s." Searches for "nitty-gritty" + "slave" and "nitty gritty" + "racist" yield lots of matches throughout the 1990s in which nitty-gritty appears un-self-consciously and seemingly nonpejoratively in discussions of slavery and/or racism—but not once in the context of its being a racist term itself or in the context of the "slave ship debris" theory.
That changes in 2002—and the change seems to have arisen exclusively in British publications. Mari-Lou A cites a detailed May 15, 2002, BBC article in her question. A Google Books search turns up two other publications from 2002 in which use of nitty-gritty is posed as having racial complications.
First, from an unidentified item seemingly by Darcus Howe, in New Statesman, volume 131 (2002) [combined snippets]:
The Wikipedia page for Darcus Howe reports that he "was a British broadcaster, writer and racial justice campaigner." New Statesman is a left-liberal British magazine, founded more than a century ago by Sidney and Beatrice Webb. Whether Howe is correct or mistaken in thinking that the entire "slave ship debris" theory was a set-up for Britain's equivalent of Fox News to run with, it is interesting that he reports not finding anyone in his "racial justice" milieu who subscribed to it in 2002.
Second, from an unidentified item in Spearhead, issues 395–404 (2002[?]) [text not shown in snippet window]:
According to the Wikipedia article about it, Spearhead "was a British far-right magazine edited by John Tyndall until his death in July 2005."
After two decades of life in a country (the U.S.) where ginning up outrage over and contempt for the supposed vileness and mendacity of one's political opponents seems to have become a crucial element in the business model of a number of news outlets, I find it not at all hard to believe that the "slave ship debris" etymological argument for nitty-gritty might have been simply a hoax—like crop circles or that story in The Onion about the U.S. Congress threatening to relocate to Charlotte or Memphis if the District of Columbia didn't build it a new state-of-the-art facility with a retractable dome (which at least one credulous official Chinese news site cited as proof of the utter corruption of the U.S. government). But however the theory arose, it has never had any serious academic support.
A Google Books chart tracking the frequency of "nitty gritty" over the years 1940–2019 suggests that any blowback against use of the term on grounds that it is racially problematic is scarcely detectable:
Even when Google Books search results are restricted to British publications, the drop over the period 2001–2008 is smaller than the drop from 1986 to 1993, when no tempest was troubling the teacup of anyone inclined to use the term nitty-gritty:
This is one prospective culture war controversy that seems not to have reached critical mass in the U.S. (At least, I haven't noticed it.) But there is still plenty of time and an endless supply of media opportunists to make it happen here if ever they don't have something brighter, shinier, or juicier to show their audience during a given news cycle.