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marrow

n.
US //ˈmɛɹoʊ// UK //mˈæɹəʊ// mar·row
  1. 1 inside bones (n.)
    B2 Upper Intermediate Medicine

    the soft, fatty substance inside your bones where blood cells are made.

    the fatty, vascular tissue found in the cavities of bones; it is the primary site of blood cell production.

    Example

    The doctor explained that the patient needed a marrow transplant to help her body make healthy blood.

    Example

    The biopsy revealed that the marrow was producing an insufficient number of red blood cells, necessitating a more aggressive treatment plan.

    Usage

    Often used as an uncountable noun in medical contexts.
    • bone marrow
  2. 2 vegetable (n.)
    B2 Upper Intermediate British English Cooking

    a large, long green vegetable with a hard skin that is related to the zucchini.

    a large, edible gourd or squash, typically of the species Cucurbita pepo, harvested when mature.

    Example

    We grew a giant marrow in the garden and stuffed it with rice and herbs for dinner.

    Example

    The local horticultural show awarded first prize to a marrow that weighed over thirty kilograms, a testament to the gardener's dedication.

    Usage

    Commonly used in British English; American speakers usually refer to similar vegetables as 'squash' or 'large zucchini'.
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  1. 3 the essence (n.)
    C1 Advanced Literary

    the most important or central part of something.

    the essential or most vital part of an idea, situation, or person.

    Example

    The book really gets to the marrow of what it means to be human.

    Example

    The philosopher's latest essay attempts to strip away the superficial arguments and reach the marrow of the ethical dilemma.
  2. 4 a friend (n.)
    C2 Proficiency Dialect British English

    a word for a friend or a work partner.

    a companion, mate, or work associate, particularly in mining or industrial contexts.

    Example

    He went down to the pub to meet his old marrow for a drink.

    Example

    In the traditional mining communities of the North East, a marrow was more than just a colleague; they were a trusted partner underground.

    Teacher's tip

    This sense is specific to Northern England, particularly the Tyneside area, and is rarely heard elsewhere.
Etymology 1

From Middle English mary, marow, marwe, marowȝ, from Old English mearg, from Proto-West Germanic maʀg, from Proto-Germanic mazgą, mazgaz, from Proto-Indo-European mosgʰos. Compare West Frisian moarch, Dutch merg, German Mark, Swedish märg, Icelandic mergur, and also Russian мозг (mozg, “brain”), Polish mózg (“brain”), Ashkun amōźã, Kamkata-viri muč, muj, Waigali muj, Persian مغز (maġz, “brain”), Sanskrit मज्जन् (majján). Doublet of maghaz.

Etymology 2

From Old Norse margr.

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