Nitty-gritty is slang for the basic facts, key details or most practical aspects.(noun)
Knowing the date, time and place of a party are an example of the nitty-gritty of planning a party.
See nitty-gritty in Webster's New World College Dictionary
Origin: orig. black slang: rhyming euphemism for shitty
See nitty-gritty in American Heritage Dictionary 4
Origin: Origin unknown.
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