What is what does it mean when a guy says cool?

When a guy says "cool," it means that he is expressing his approval or agreement with something that has been said or done. The word cool is often used as a casual way of acknowledging something positive or interesting, such as a good idea, a fun activity, or a stylish outfit. Additionally, depending on the context and tone, saying "cool" can also indicate a lack of emotion or enthusiasm. Overall, the meaning of "cool" can vary depending on the situation and the person who is using it.