The term 'notorious' refers to being famous or well-known, typically for negative reasons. The correct answer is B, 'infamous', which directly aligns with the meaning of notorious. Option A, 'celebrated', implies positive recognition, which contradicts the meaning of notorious. Option C, 'honorable', suggests a person of high moral standards, which is also opposite to notorious. Option D, 'unknown', does not fit as it implies a lack of recognition.