Lexicon plays an essential role in natural language processing systems and specially the machine translation systems, because it provides the system's components with the necessary information for the translation process. Although there have been a number of researches in natural language processing field, not enough attention has been given to the importance of the lexicon and specially the Arabic lexicon. The aim of this paper is to determine the basic requirements to build a lexicon used for machine translation purpose from Arabic to English language and organize lexicon contents in such form to provide efficient memory usage and minimize the retriever time, and also determine how can we retrieve these tokens from the lexicon after analyzing them by using morphology analyzer.
The proposed lexicon based on the Arabic root in storing its words, it use the logical terms to represent its knowledge and uses B+tree data structure to organize this knowledge. And the proposed lexicon has been built by using the visual logical programming language (Visual Prolog).