nitty-gritty vs kernel

nitty-gritty and kernel both are nouns.

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

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

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

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

nitty-gritty (noun)	kernel (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
	a single whole grain of a cereal
	the inner and usually edible part of a seed or grain or nut or fruit stone