The Collaborative International Dictionary of English v.0.48:

Sensitivity \Sen`si*tiv"i*ty\, n.
   The quality or state of being sensitive; -- used chiefly in
   science and the arts; as, the sensitivity of iodized silver.
   [1913 Webster]

         Sensitivity and emotivity have also been used as the
         scientific term for the capacity of feeling. --Hickok.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sensitivity
    n 1: (physiology) responsiveness to external stimuli; the
         faculty of sensation; "sensitivity to pain" [syn:
         sensitivity, sensitiveness, sensibility]
    2: the ability to respond to physical stimuli or to register
       small physical amounts or differences; "a galvanometer of
       extreme sensitivity"; "the sensitiveness of Mimosa leaves
       does not depend on a change of growth" [syn: sensitivity,
       sensitiveness]
    3: sensitivity to emotional feelings (of self and others) [syn:
       sensitivity, sensitiveness]
    4: susceptibility to a pathogen [syn: sensitivity,
       predisposition]
    5: the ability to respond to affective changes in your
       interpersonal environment [syn: sensitivity,
       sensitiveness] [ant: insensitiveness, insensitivity]