Jet Li about Kung Fu:

Nowadays, one associates the word, “kung-fu,” with punches, kicks, martial arts champions, fighting. But the original meaning of “kung-fu” was never intended to describe martial arts in any way. Kung-fu originally referred to the time and energy spent in learning something.

A successful chef expends lots of “kung-fu” to cook the tastiest dishes. A doctor undergoes considerable “kung-fu” to be able to take care of sick people. A martial artist uses lots of “kung-fu” in practicing his physical forms so he may display them to audiences one day.

The term “kung-fu” was first broached to Western audiences by Bruce Lee when he stepped into the spotlight and used it to describe his martial arts. From there, a misconception arose and people began using “kung-fu” to refer to Bruce Lee, martial arts, punches, kicks, and the whole related system".