ENGLISH
REFERENCE

lightweight

n. · adj. · v.
US //ˈɫaɪtˈweɪt// UK //lˈaɪtweɪt// light·weight
  1. 1 combat sports (n.)
    B2 Upper Intermediate Sport

    a person who competes in a specific weight class, usually between featherweight and welterweight.

    a professional weight division in sports such as boxing, wrestling, and MMA, typically falling between featherweight and welterweight.

    Example

    The lightweight won the championship after a very fast and exciting fight.

    Example

    The lightweight division remains one of the most competitive in the sport, requiring a perfect balance of speed and punching power.

    Usage

    Often used as a modifier before another noun, like 'lightweight champion'.
  2. 2 unimportant person (n.)
    C1 Advanced Informal

    someone who is not important or does not have much influence or ability.

    a person of little importance, influence, or intellectual depth.

    Example

    The other politicians ignored him because they thought he was a lightweight.

    Example

    Despite his family connections, he was regarded as a political lightweight who lacked the gravitas to lead the party.

    Teacher's tip

    This is the metaphorical opposite of a 'heavyweight' in a professional or intellectual context.
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  1. 3 alcohol tolerance (n.)
    B2 Upper Intermediate Informal

    a person who gets drunk very quickly after only a small amount of alcohol.

    an individual with a low physiological tolerance for alcohol.

    Example

    I am such a lightweight that I feel dizzy after just one glass of wine.

    Example

    He earned a reputation as a lightweight among his colleagues after falling asleep at the first office happy hour.

    Teacher's tip

    This is a very common informal usage in social settings, often used in a lighthearted or self-deprecating way.

  2. 4 not heavy (adj.)
    B2 Upper Intermediate

    made of thin or light material; not weighing very much.

    having relatively little weight; specifically designed to be portable or easy to move.

    Example

    You should bring a lightweight jacket because it might get cool in the evening.

    Example

    The hikers preferred lightweight carbon-fiber poles to reduce the strain on their joints during the long ascent.
  3. 5 computing (adj.)
    C1 Advanced Technical Computing

    software that is small, fast, and does not use much of a computer's power.

    referring to software or protocols designed to have a small footprint and minimal impact on system resources.

    Example

    I use a lightweight browser because my old laptop cannot run the heavy ones.

    Example

    The developers opted for a lightweight framework to ensure the application remained responsive even on older mobile hardware.
  4. 6 to make lighter (v.)
    C2 Proficiency Technical

    to make something weigh less by using different materials.

    to reduce the weight of a vehicle or structure, typically to improve performance or fuel efficiency.

    Example

    The engineers had to lightweight the car to meet the new racing rules.

    Example

    By lightweighting the chassis with aluminum alloys, the manufacturer significantly improved the vehicle's power-to-weight ratio.
Origin

From light (“not heavy”, adjective) + weight (noun).

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