ADJECTIVE (2)

1. not responsive to physical stimuli;
- Example: "insensitive to radiation"

2. deficient in human sensibility; not mentally or morally sensitive;
- Example: "insensitive to the needs of the patients"

The Collaborative International Dictionary of English v.0.48:

Insensitive \In*sen"si*tive\, a.
   Not sensitive; wanting sensation, or wanting acute
   sensibility. --Tillotson. --Ruskin.
   [1913 Webster]

WordNet (r) 3.0 (2006):

insensitive
    adj 1: not responsive to physical stimuli; "insensitive to
           radiation" [ant: sensitive]
    2: deficient in human sensibility; not mentally or morally
       sensitive; "insensitive to the needs of the patients" [ant:
       sensitive]