What does "get one's back" mean?
Native speaker’s answer
Rebecca
To "get/have someone's back" is an idiom that means you are willing to help and defend someone in need, usually someone close to you. "Have someone's back" is a general expression. Ex: I knew she had my back when I forgot my wallet and she paid for my lunch. Ex: I have my brother's back, I always make sure he is doing well.