The original idea of kung fu has nothing to do with the martial arts. “Kung” means the time devoted to working on something. “Fu” means a tough guy or an intelligent person. When put together, the phrase describes somebody who works hard at a task. Chinese people even use this to make jokes about their friends, e.g. “How good is your kung fu in bed with your girlfriend?”

However, it can also be used as an equivalent to Eastern martial arts. Since Bruce Lee came to the West, it has been associated with the Chinese style of martial arts. Now it is another way of saying martial arts or self-defence.