effector

/IH0 F EH1 K T ER0/
noun
  1. 1

    Any muscle, organ etc. that can respond to a stimulus from a nerve.

  2. 2

    The part of a nerve that carries a stimulus to a muscle etc.

  3. 3

    Any small molecule that effects the function of an enzyme by binding to an allosteric site.

  4. 4

    An actuator.

Source: https://en.wiktionary.org/wiki/effector