highly 'sensitive' information [=information that could be harmful if many people knew it; information that should be kept secret]
She's painfully/overly 'sensitive about' her looks. [=she cares very/too much about what people say or think about her looks]
Now that I'm older, I'm more 'sensitive to' (the) cold. [=I feel colder in cold surroundings now than I did in the past]