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bladder

n.
US //ˈbɫædɝ// UK //blˈædɐ// blad·der
  1. 1 body organ (n.)
    B2 Upper Intermediate Medicine

    the organ in your body that holds urine before it leaves the body.

    the urinary bladder; a muscular sac in the pelvis that stores urine excreted by the kidneys.

    Example

    Drinking a lot of water will fill your bladder quickly.

    Example

    The surgeon noted that the patient's bladder was slightly inflamed, likely due to a chronic infection that had gone untreated for several months.
    • urinary bladder
  2. 2 flexible container (n.)
    C1 Advanced Technical

    a flexible bag inside something that holds air or liquid, like inside a football.

    an inflatable internal bag or sac used to contain gas or liquid within a larger structure.

    Example

    The football wouldn't stay inflated because the rubber bladder inside was leaking.

    Example

    Modern hydration packs feature a heavy-duty plastic bladder that can withstand significant pressure without bursting during strenuous outdoor activities.
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  1. 3 plant/animal sac (n.)
    C2 Proficiency Technical Science

    a small, hollow part of a plant or sea animal that is filled with air.

    a hollow, air-filled organ in certain plants or aquatic animals, often providing buoyancy.

    Example

    The seaweed has small bladders that help it float on the surface of the water.

    Example

    The gas bladder of the fish allows it to maintain its depth in the water column without expending excessive energy on swimming.
    • vesicle
    • air sac
Origin

From Middle English bladdre, bleddre, bladder, bledder, from Old English blæddre, a variant of blǣdre, blēdre (“blister, bladder”), from Proto-West Germanic blādrā, from Proto-Germanic blēdrǭ, *bladrǭ (“blister, bladder”).

Idioms1 entry

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