The Vietnamese word "phát sốt" means "to have a fever" or "to run a temperature." It is used to describe a condition when someone's body temperature rises above the normal level, usually indicating that the body is fighting an infection or illness.
While "phát sốt" primarily refers to having a fever, it can sometimes be used metaphorically in phrases to indicate excitement or intense emotion. For example, "phát sốt vì điều gì đó" could mean "to be extremely excited about something."