ENGLISH
REFERENCE

flex

v. · n.
US //ˈfɫɛks// UK //flˈɛks// flex
  1. 1 to tighten muscles (v.)
    B2 Upper Intermediate

    to tighten your muscles to show how strong you are.

    to contract or tighten a muscle, typically to demonstrate strength or prepare for physical exertion.

    Example

    The bodybuilder began to flex his arms as soon as he stepped onto the stage.

    Example

    Before the heavy lifting began, the athlete paused to flex his quadriceps, ensuring the muscles were warm and responsive.
  2. 2 to bend (v.)
    B2 Upper Intermediate

    to bend something that is flexible.

    to bend a functional part or a flexible material without breaking it.

    Example

    You can flex the plastic ruler quite a bit before it snaps.

    Example

    Modern aircraft wings are designed to flex significantly during turbulence to absorb structural stress.
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  1. 3 to show off (v.)
    B2 Upper Intermediate Slang Informal

    to show off your money, success, or expensive things to impress people.

    to boast or flaunt one's wealth, status, or achievements in an ostentatious manner.

    Example

    He bought a luxury watch just to flex on his old classmates.

    Example

    Social media influencers often use their platforms to flex their lifestyle, posting photos of private jets and designer clothing to maintain their brand image.
  2. 4 a boast (n.)
    B2 Upper Intermediate Slang Informal

    an act of showing off or something that is impressive.

    an instance of boasting or an ostentatious display intended to impress others.

    Example

    Posting your high test scores on the group chat was a bit of a flex.

    Example

    Mentioning his connection to the CEO during the first five minutes of the interview was a subtle but clear flex.

    Usage

    Often used in the phrase 'weird flex but okay' to describe a strange boast.
  3. 5 electrical cord (n.)
    C1 Advanced British English

    a flexible electrical wire or cord used for a tool or lamp.

    a flexible, insulated electrical cable, typically connecting an appliance to a mains plug.

    Example

    The iron has a long flex so you can reach across the whole board.

    Example

    The safety inspector noted that the flex on the industrial vacuum was frayed and required immediate replacement.
Origin

From Latin flexus, past participle of flecto (“to bend”).

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