marrow vs bare bones

marrow and bare bones both are nouns.

Word	Noun	Adjective	Verb	Adverb
marrow	Yes	No	No	No
bare bones	Yes	No	No	No

As nouns, bare bones is a hyponym of marrow; that is, bare bones is a word with a more specific, narrower meaning than marrow:

marrow: the choicest or most essential or most vital part of some idea or experience
bare bones: (plural) the most basic facts or elements

Other hyponyms of marrow include hypostasis, haecceity, quiddity, quintessence, stuff.

marrow (noun)	bare bones (noun)
the fatty network of connective tissue that fills the cavities of bones	(plural) the most basic facts or elements
the choicest or most essential or most vital part of some idea or experience
large elongated squash with creamy to deep green skins
very tender and very nutritious tissue from marrowbones
any of various squash plants grown for their elongated fruit with smooth dark green skin and whitish flesh