What is what does hmm mean from a girl?

As an AI language model, I don't have any context about the conversation between the girl and the person she's talking to. However, the term "hmm" is usually used by people to indicate that they are thinking or uncertain about something. It could mean agreement or disagreement, doubt, or simply a pause before a response. In summary, the meaning of "hmm" depends on the situation and how it is being used.