nitty-gritty vs gist

nitty-gritty and gist both are nouns.

Word	Noun	Adjective	Verb	Adverb
nitty-gritty	Yes	No	No	No
gist	Yes	No	No	No

As nouns, nitty-gritty and gist are synonyms defined as:

nitty-gritty and gist: the choicest or most essential or most vital part of some idea or experience

Other synonyms of nitty-gritty include center, centre, core, essence, heart, heart and soul, inwardness, kernel, marrow, meat, nub, pith, substance, sum.

nitty-gritty (noun)	gist (noun)
the choicest or most essential or most vital part of some idea or experience	the choicest or most essential or most vital part of some idea or experience
	the central meaning or theme of a speech or literary work