The ability to be aware of (and, usually, react with regard to) the feelings of others.
The quality or degree of being sensitive.
The ability to perceive sensation.
emotional sensitivity.
the condition of being susceptible; vulnerability
Being vulnerable to a treatment (usually an antibiotic or antifungal); also, the degree of such vulnerability (i.e., weak, moderate, or strong).
electric susceptibility, a measure of how easily a dielectric polarizes in response to an external electric field (compare permittivity).