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reflex - definition and synonyms


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noun [countable] reflex pronunciation in American English /ˈriˌfleks/
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  1. 1
    a movement that your muscles make without you thinking about it or being able to control it

    The blinking reflex can be set off by bright light.

    The doctor tested all his reflexes.

  2. 2
    a way of reacting to something that you do very quickly, without thinking about it

    Boxers need to have very quick reflexes.

    1. a.
      [only before noun] a reflex movement or action is one that you do very quickly, without thinking about it

      The goalkeeper made a couple of excellent reflex saves.


sea lion

in an online conversation, repeatedly asking a person questions which suggest that you are interested in what they are talking about, but are actually intended to annoy them

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