This chapter starts with a caveat: linguists sometimes object to the use of Formal Concept Analysis (FCA) for linguistic applications! The reason for this is that the notion of “concept” in FCA does not correspond exactly to a notion of “concept” as developed by linguistic and philosophical theories. For example, Frege’s  notions of “Sinn” (sense) and “Bedeutung” (reference) appear on first sight to contradict FCA concepts because he explains that the words “morning star” and “evening star” have the same reference but a different sense. Thus if “reference” is taken to mean “extension” of a concept and “sense” to mean “intention,” then this would contradict the FCA claim that if two concepts have the same extension they also must have the same intension with respect to a given formal context. But this apparent contradiction can in fact be resolved because it is more a misunderstanding than a contradiction.