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principle - definition and synonyms

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noun     principle pronunciation in British English
Word Forms
  1. 1
    [countable] a basic belief, theory, or rule that has a major influence on the way in which something is done

    Excellent customer service should be our guiding principle.

    principle of:

    It is a basic principle of English law that a person is innocent until proven guilty.

    principle that:

    the principle that education should be free to everyone

    1. a.
      [often plural] one of the major ideas or theories that a system of beliefs is based on, for example in religion or politics

      Marxist/Buddhist/democratic principles

      the principles and ideals that the party stands for

  2. 2
    [countable] [usually plural] a basic rule or belief about what is right and morally good, that influences the way that you behave and the way that you treat other people

    He seems to have absolutely no principles.

    against someone’s principles:

    It was against their principles to join the armed forces.

    stick to/stand by your principles:

    Bennett stuck to his principles, and refused to name the source of his information.

    1. a.
      [uncountable] morally correct behaviour

      a woman of principle

      on principle:

      We are opposed on principle to any collaboration with terrorists.

      a point/matter/issue of principle:

      There are some basic issues of principle relating to the debate about abortion.

  3. 3
    [countable] a scientific theory or basic natural law that explains the way in which something works

    Windmills differ in design, but all operate on exactly the same principle.

    Heisenberg’s Uncertainty Principle

    principle of:

    It was Darwin who first identified the ‘principle of female choice’.

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