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REFERENCE

fluid

n. · adj.
US //ˈfɫuəd// UK //flˈuːɪd// flu·id
  1. 1 liquid or gas (n.)
    B2 Upper Intermediate Technical Science

    any substance that flows easily and takes the shape of its container, such as water or air.

    a substance, such as a liquid, gas, or plasma, that deforms under shear stress and conforms to the shape of its container.

    Example

    The mechanic checked the levels of the brake fluid in the car.

    Example

    The laboratory equipment was designed to measure the viscosity of various industrial fluids under extreme pressure conditions.
  2. 2 medical liquids (n.)
    C1 Advanced Technical Medicine

    liquids given to a patient, often through a tube in the arm.

    intravenous solutions administered to a patient to maintain hydration or deliver medication.

    Example

    The doctor said the patient needed more fluids to recover from the fever.

    Example

    The nursing staff monitored the administration of intravenous fluids to ensure the patient remained stable after the surgery.
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  1. 3 changing easily (adj.)
    B2 Upper Intermediate

    likely to change; not fixed or settled.

    subject to change or transition; characterized by a lack of fixed structure.

    Example

    The travel plans are still fluid because we haven't booked the flights yet.

    Example

    The political situation remained fluid as negotiators struggled to reach a consensus before the midnight deadline.
  2. 4 smooth motion (adj.)
    B2 Upper Intermediate

    moving in a smooth and beautiful way.

    characterized by a smooth, elegant, and continuous quality of motion.

    Example

    The dancer's movements were fluid and graceful.

    Example

    The athlete's fluid running style allowed him to maintain a high pace without appearing to exert significant effort.
  3. 5 available cash (adj.)
    C1 Advanced Formal Technical

    describes money or assets that can be used or moved easily.

    referring to assets that are easily converted into cash without significant loss of value.

    Example

    The company needs to keep some fluid assets to pay for unexpected repairs.

    Example

    The investment firm advised the client to maintain a portion of their portfolio in fluid capital to respond to market volatility.
Origin

From Middle English fluid, from Latin fluidus (“flowing; fluid”), from Latin fluō (“to flow”), from Proto-Indo-European bʰleh₁- (“to swell; surge; overflow; run”). Akin to Ancient Greek φλύειν (phlúein, “to swell; overflow”). Not related to English flow, which is a native, inherited word from plew-, but is distantly related from English bleat.

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