The Collaborative International Dictionary of English v.0.48:
Distinctiveness \Dis*tinc"tive*ness\, n. State of being distinctive. [1913 Webster]WordNet (r) 3.0 (2006):
distinctiveness n 1: a distinguishing trait [syn: peculiarity, specialness, specialty, speciality, distinctiveness] 2: utter dissimilarity [syn: disparateness, distinctiveness]