jiāo​gǎn​zuò​yòng

sympathetic action

  1. sympathetic
    (physiology) relating to or denoting the part of the autonomic nervous system that prepares the body for action; sympathetic
  2. function
    the natural purpose or activity of something, such as a biological or chemical process; often used as a suffix to mean "-ation" or "-ing" as in 消化 xiāo​huà plus this word for "digestion"