Non-Arabic Words in Arabic of the Fourth Century AH'A Study in Ahsan Attaqaseem fee Marefet Ellaqaleem of Almaqdisi) This research applied the theory of influence and vulnerability between languages.it was interested in the branch of Geographical linguistics and the idea of building the historical linguistic lexicon for non Arabic wards. interest in the industry of Atlas of linguistic Geography, The research cam out in anintroduction' preface and two chapters' the first is entitled linguistic phenomena in AhssanAttaqasseem' and the second record the most prominent findingings and recommendations of the recearch