This dictionary undertakes, for the first time, to group the substantives and adjectives in the Arabic Koran by topics, with glosses in English. The categories are partly derived from nature such as Astronomy, Metals or Human Sexuality, partly they reflect the great themes of the text, such as Guidance and Straying or Obedience and Disobedience. An English index enables the user to check if a certain concept occurs and how it is expressed in the Arabic Koran.