Definition of "Marrow" :

noun: the fatty network of connective tissue that fills the cavities of bones

noun: the choicest or most essential or most vital part of some idea or experience

noun: large elongated squash with creamy to deep green skins

noun: very tender and very nutritious tissue from marrowbones

noun: any of various squash plants grown for their elongated fruit with smooth dark green skin and whitish flesh