The Collaborative International Dictionary of English v.0.48:
Unambiguity \Un*am`bi*gu"i*ty\, n. Absence of ambiguity; clearness; perspicuity. [1913 Webster]WordNet (r) 3.0 (2006):
unambiguity n 1: clarity achieved by the avoidance of ambiguity [syn: unambiguity, unequivocalness] [ant: ambiguity, equivocalness]