1 a : the tendency to become upset about things that are done to you, are said about you, or relate to you [noncount] ▪ I was surprised by her extreme sensitivity about even the smallest suggestions that we made. — often + to ▪ his sensitivity to criticism [count] ▪ Their sensitivities were inflamed by his remarks. [=they became very upset by his remarks]
b [noncount] : the tendency to cause people to be upset
▪ the racial sensitivity of this issue [=the tendency of people of certain races to become upset about this issue] ▪ This is a matter of great political sensitivity. 2 a : an awareness and understanding of the feelings of other people [noncount] ▪ He handled the situation with great sensitivity. ▪ Her decision shows a lack of sensitivity. ▪ I would have appreciated a little more sensitivity from you. [singular] — often + to ▪ She has shown a great sensitivity to the needs of her students.
b : an awareness of the details or qualities of something — often + to ▪ He displays a remarkable sensitivity to the subtle nuances of language. 3 : the quality of being easily affected by something in a bad or unpleasant way [noncount] ▪ skin sensitivity [=the skin's tendency to react in a bad way to substances that touch it] ▪ drug sensitivity = sensitivity to drugs/medications [count] ▪ He has chemical sensitivities. [=his body reacts badly to certain chemicals] ▪ He has food sensitivities. [=he can't eat certain kinds of food] — often + to ▪ a sensitivity to light/pollen 4 [singular] : the ability to express your thoughts and feelings through writing, music, etc.
▪ Her singing is characterized by a rich emotional sensitivity. 5 [noncount] : the quality of needing to be handled in a careful or secret way
▪ the sensitivity of this document/data 6 [noncount] technical : the ability of a device to sense very small changes in something
▪ The new refinements have improved the sensitivity of the motion detector.