sen·si·tize 
(s
ĕn
s
ĭ-t
īz
′)
v. sen·si·tized, sen·si·tiz·ing, sen·si·tiz·es
v.tr.1. To make sensitive: "Solitude had sensitized him to the roughness of other people" (Jeffrey Eugenides).
2. To make (a film or plate) sensitive to light, especially to light of a specific wavelength.
3. To make hypersensitive or reactive to an antigen, such as pollen, especially by a second or repeated exposure.
v.intr. To become sensitive or hypersensitive.
[SENSIT(IVE) + -IZE.]
sen′si·ti·zation (-tĭ-zāshən) n.
sensi·tiz′er n.