“Nitty-gritty” means the basic essentials, the heart of the matter, the harsh realities, the most vital details, the most practical part of something. It’s often used in this phrase: “getting down to the nitty-gritty.”
There exist several theories about the source of “nitty-gritty.” The most prevalent seems to be that it’s a derogatory reference to the English slave trade of the 1700s, that it was a term for the unimportant debris left at the bottom of ships after the slaves had been removed and that the meaning was extended to include the slaves themselves.
No evidence exists to support the suggestion that “nitty-gritty” is connected in any way with slave ships. It may have originated in the USA as an African-American expression used by black jazz musicians, but that’s as close as it gets to slavery. It isn’t even recorded in print until the 1930s, long after slave ships had disappeared.
The first print reference of the phrase appears to be from the New York Catalog of Copyright Entries, Part 3 – Musical Compositions, 1937. That lists a song titled “That Nitty Gritty Dance” which was copyrighted by Arthur Harrington Gibbs. The next appearance in print consisted of several in 1956, such as in Alice Childress’ novel Like One of Family.
Other theories suggest that “nitty-gritty” refers to head lice, or “nits,” or to ground corn, known as “grits.” But there’s no hard evidence to support either of these.
We don’t know where it came from. It’s one of many phrases that use rhyming reduplication, for example, namby-pamby or willy-nilly. It could well be that the rhyme was formed as a simple extension of the US adjective “gritty,” meaning determined or plucky.
Wikipedia lists the following uses of the phrase as names or titles:
—Nitty Gritty (1957–1991), Jamaican reggae singer
—The Nitty Gritty, a 1963 song recorded by Shirley Ellis
—Nitty Gritty Dirt Band, an American country music band
I like the down and dirty sound of the Nitty Gritty Dirt Band. But, since I know a lot more about cats than I do about music, I’ll change the phrase. In my house from now on, it will be “kitty-gritty.” Kitty litter kicked out onto the tiles is very gritty under bare feet.