What does "thick-skinned" mean?

Native speaker’s answer
Rebecca
"Thick-skinned" means tough, resilient, or insensitive. Criticism or difficult things don't bother you much. Here he's saying that although he seems "tough" he is actually sensitive. Ex: After staying in a college dorm, I became thick-skinned. Ex: My sister has thick-skin. So she can handle people insulting her.