The task of automatically characterizing word meaning in text is typically modeled as word sense disambiguation (WSD): given a list of senses for target lemma w, the task is to pick the best-fitting sense for a given occurrence of w. The list of senses is usually taken from an online dictionary or thesaurus.
clear cut sense boundaries are sometimes hard to define, and the meaning of words depends strongly on the context in which they are used (Cruse, 2000;Hanks, 2000).