Allahu akbar

The Takbīr (تَكْبِير), also transliterated Tekbir or Takbeer, is the term for the Arabic phrase Allāhu akbar (), usually translated as "God is [the] greatest". It is a common Islamic Arabic expression, used in various contexts by Muslims; in formal prayer, in the call for prayer (adhān), as an informal expression of faith, in times of distress, or to express resolute determination or defiance.

The form Allāhu is the nominative of Allah, meaning "God". In the context of Islam, it is the proper name of God. The form is the elative of the adjective kabīr, meaning "great", from the Semitic k-b-r. As used in the Takbīr it is usually translated as "greatest", but some authors prefer "greater". The phrase is often transliterated less accurately as Allah akbar.

The term Takbīr itself is the stem II verbal noun (tafʿīlun) of the triliteral root k-b-r, meaning "great", from which Akbar "greater" is derived.

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