If you are sensitive to other people's needs, problems, or feelings, you show understanding and awareness of them.

If you are sensitive about something, you are easily worried and offended when people talk about it.

A sensitive subject or issue needs to be dealt with carefully because it is likely to cause disagreement or make people angry or upset.

Sensitive documents or reports contain information that needs to be kept secret and dealt with carefully.

Something that is sensitive to a physical force, substance, or treatment is easily affected by it and often harmed by it.

A sensitive piece of scientific equipment is capable of measuring or recording very small changes.