the nitty-gritty

Example: “Let's skip the introductions and get down to the nitty-gritty.”

Origin: A widely repeated claim holds that the phrase comes from the debris supposedly left in the hold of a slave ship after the enslaved people forced to cross the Atlantic in it had been removed. The theory does not hold up: the phrase is not attested in print until the Pittsburgh Courier, an African American newspaper, in 1940 — centuries after the transatlantic slave trade, with no documented link connecting the two, and the earliest known claim tying it to slave ships only surfaces in a British newspaper in 2002. The real history is less dramatic and less certain: "nitty-gritty" most likely arose among Black American jazz musicians as a rhyming elaboration of "gritty" — something rough, real, or unglamorous — with "nitty" added purely for the sound of the doubled beat, the same way English forms many other reduplicated pairs like "itsy-bitsy" or "super-duper."