A lexicon stored on a computer readable medium and used by language processing systems. The lexicon can store word information in a plurality of data fields associated with each entered word. The data fields can include information on spelling and grammar, parts of speech, steps that the entered word can be transformed into another word, a word description, and a segmentation for a compound word. Information that cannot be stored in the lexicon can be stored in an intermediate indexes table. Associated methods of constructing, updating and using the lexicon are introduced.