말이 떨어지자 무섭게라는 뜻. 선문답 (禪門答)에서 말이 떨어지자마자 단박에 깨치는 경우에 흔히 쓰는 말

Spontaneity: A spontaneous understanding, realization, or response upon hearing something, such as sudden enlightenment during Seon or Zen dialogue between the master and disciple.