nitty-gritty
adjEtymology Of uncertain origin; said to have been first used by black jazz musicians from the United States, the word is perhaps a reduplication of gritty (“resembling grit”) (ultimately from Proto-Germanic *greutą (“grit”), from Proto-Indo-European *gʰrewd-) with alteration of the first syllable. An urban legend links the origin of the word to the debris remaining in the holds of slave ships after the slaves had been disembarked, but there is no evidence for this. The word is not attested early enough to have been associated with slavery.
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Colloquial Dealing with something in great depth.
- 1976, United States. National Commission on Arthritis and Related Musculoskeletal Diseases, Arthritis - Out of the Maze We deal with them at a very, very nitty gritty level, and we deal with the results of years and years of problems that they've had in the past.