An instinct is something you don't need to learn — it happens naturally, without you even thinking about it. Babies cry by instinct, and ducks follow their mother by instinct.

Animals and humans learn a lot of things from other animals and humans. But if there isn't any learning involved, then the behavior is an instinct. Instincts come naturally, like a baby's desire to feed. Some behaviors are a combination of instinct and learned behavior, like language. Others happen without any teaching at all, like the instinct to run when you see a big, hungry looking bear. When you see the word instinct, think natural response.

Definitions of instinct
  1. noun
    inborn pattern of behavior often responsive to specific stimuli
    “the spawning instinct in salmon”
    “altruistic instincts in social animals”
    synonyms: inherent aptitude
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    (psychoanalysis) primitive instincts and energies underlying all psychic activity
    type of:
    inherent ability
  2. adjective
    (followed by `with')deeply filled or permeated
    “words instinct with love”
    synonyms: replete
    containing as much or as many as is possible or normal
Word Family

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