Extremism

Extremism is the opposite of centrism.

Extremism on Wikipedia

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Extremism is "the quality or state of being extreme" or "the advocacy of extreme measures or views".

The term is primarily used in a political or religious sense, to refer to an ideology that is considered (by the speaker or by some implied shared social consensus) to be far outside the mainstream attitudes of society. It can also be used in an economic context. The term is usually meant to be pejorative. However, it may also be used in a more academic, purely descriptive, non-condemning sencse.

Extremists views are typically contrasted with those of moderates. In Western countries for example, in contemporary discourse on Islam or on Islamic political movements, the distinction between extremist and moderate Muslims is commonly stressed.

Political agendas perceived as extremist often include those from the far-left politics or far-right politics as well as radicalism, reactionism, fundamentalism and fanaticism.