Adding a medical lexicon to an English Parser.

We present a heuristic method to map lexical (syntactic) information from one lexicon to another, and apply the technique to augment the lexicon of the Link Grammar Parser with an enormous medical vocabulary drawn from the Specialist lexicon developed by the National Library of Medicine. This paper presents and justifies the mapping method and addresses technical problems that have to be overcome. It illustrates the utility of the method with respect to a large corpus of emergency department notes.