ENGLISH
REFERENCE

flush

v. · n. · adj.
US //ˈfɫəʃ// UK //flˈʌʃ// flush
  1. 1 to clean with water (v.)
    A2 Elementary

    to clean a toilet or a pipe by sending a large amount of water through it.

    to cleanse or empty a space, especially a toilet or plumbing system, by a sudden rush of water.

    Example

    Don't forget to flush the toilet after you use it.

    Example

    The plumber had to flush the entire heating system to remove the buildup of rust and debris from the old pipes.
  2. 2 to turn red (v.)
    B1 Intermediate

    to become red in the face because you are embarrassed, angry, or hot.

    to become suffused with blood in the face, typically as a physiological response to emotion or temperature.

    Example

    She felt her cheeks flush when the teacher called her name in front of the class.

    Example

    He began to flush with anger as the witness continued to contradict the evidence presented earlier in the trial.
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  1. 3 to force out of hiding (v.)
    B2 Upper Intermediate

    to force a person or animal to leave a hiding place.

    to cause a person or animal to leave a place of concealment or cover.

    Example

    The dogs were used to flush the birds out of the tall grass.

    Example

    The investigators hoped that the new evidence would flush the suspect out of hiding before he could flee the country.
  2. 4 to clear data (v.)
    C1 Advanced Technical Computing

    to clear temporary data from a computer's memory.

    to clear a buffer or cache of its contents, often by writing the data to a more permanent storage location.

    Example

    You might need to flush your browser cache to see the changes on the website.

    Example

    The system is designed to flush the write buffer to the disk every few seconds to prevent data loss during a power failure.
  3. 5 a red glow (n.)
    B2 Upper Intermediate

    a red colour that appears on your skin.

    a reddening of the face or skin, caused by a rush of blood.

    Example

    A slight flush appeared on his face when she complimented his work.

    Example

    The fever left a deep flush on the child's cheeks, despite her hands feeling quite cold to the touch.
  4. 6 cards of the same suit (n.)
    B2 Upper Intermediate

    a set of cards in a game that are all the same type, like all hearts.

    a hand of cards all of the same suit.

    Example

    He won the poker game because he had a royal flush.

    Example

    She realised too late that her opponent was likely holding a flush, given the way he had been betting since the turn.

  5. 7 level or even (adj.)
    B2 Upper Intermediate

    being at the same level as another surface so that it is smooth.

    aligned or even with an adjacent surface; forming a continuous plane.

    Example

    Make sure the cupboard door is flush with the wall.

    Example

    The carpenter spent hours ensuring the new floorboards were perfectly flush with the existing threshold to avoid a tripping hazard.
  6. 8 having plenty of money (adj.)
    C1 Advanced Informal

    having a lot of money, usually for a short time.

    having a large amount of money; affluent or well-supplied.

    Example

    I've just been paid, so I'm feeling quite flush this weekend.

    Example

    After winning the lottery, they were suddenly flush with cash and began planning an expensive trip around the world.
Etymology 1

From Middle English flusshen, fluschen, of uncertain origin. Compare dialectal flusk (“to fly at, startle a bird out of the bush”) and flusker (“to flutter, fly irregularly”). Perhaps related to Middle English flasshen, flasschen, flaschen, see flash; or a Middle English blend of flowen (“to flow”) + guschen (“to gush”). Compare Saterland Frisian flutskje, German Low German flutschen, German flutschen.

Etymology 2

Same as Etymology 3, according to The American Heritage Dictionary of the English Language.

Etymology 3

Probably from Etymology 1, according to The American Heritage Dictionary of the English Language.

Etymology 4

Various similar terms are found in dialectal English and Scots as flash and flosh (older Scots flosche), and the variation goes back to Middle English flushe, flosche, flashe, flaske. The DSL suggests a relation between flush, English flash (“pool”), and Middle English flosche, but influence from other water-related senses of flush and flash is also conceivable.

Etymology 5

Probably from Middle French flus (“flow”), cognate with flux.

Idioms2 entries

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