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noun \ˈswich\

Simple Definition of switch

  • : a small device that starts or stops the flow of electricity to something (such as a lamp or a machine) when it is pressed or moved up and down

  • : a sudden change from one thing to another

  • : a device for moving the rails of a track so that a train may be turned from one track to another

Full Definition of switch

  1. 1 :  a slender flexible whip, rod, or twig <a riding switch>

  2. 2 :  an act of switching: asa :  a blow with a switchb :  a shift from one to anotherc :  a change from the usual <that outfit is a switch>

  3. 3 :  a tuft of long hairs at the end of the tail of an animal (as a cow) — see cow illustration

  4. 4 :  a device made usually of two movable rails and necessary connections and designed to turn a locomotive or train from one track to another

  5. 5 :  a device for making, breaking, or changing the connections in an electrical circuit

  6. 6 :  a heavy strand of hair used in addition to a person's own hair for some coiffures

Examples of switch

  1. She flicked a switch and turned the lamp on.

  2. He threw the switch to stop the machine.

Origin of switch

perhaps from Middle Dutch swijch twig

First Known Use: 1592




Simple Definition of switch

  • : to make a change from one thing to another : to start doing or using something that is different

  • : to make a change from one thing to another by turning or pushing a button or moving a switch, lever, etc.

  • : to change or replace (something) with another thing

Full Definition of switch

  • transitive verb
    1. 1 :  to strike or beat with or as if with a switch

    2. 2 :  whisk, lash <a cat switching its tail>

    3. 3a (1) :  to turn from one railroad track to another :  shunt (2) :  to move (cars) to different positions on the same track within terminal areasb :  to make a shift in or exchange of <switch seats>

    4. 4a :  to shift to another electrical circuit by means of a switchb (1) :  to operate an electrical switch so as to turn (as a device) on or off —usually used with on or off (2) :  to change to or from an active state —usually used with on or off <switched on the gene>

    5. intransitive verb
    6. 1 :  to lash from side to side

    7. 2 :  to make a shift or exchange

    switch·able play \ˈswi-chə-bəl\ adjective
    switch·er noun

    Examples of switch

    1. I switched to a new doctor.

    2. He kept switching back and forth between topics.

    3. She switched back to her original insurance company.

    4. We switched over to a different telephone service.

    5. Why did you switch jobs?

    Circa 1611

    First Known Use of switch

    circa 1611

    Seen and Heard

    What made you want to look up switch? Please tell us where you read or heard it (including the quote, if possible).


    February 11, 2016

    the holder of an office

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