robotmatrix.org

Introduction

ANSI/RIA R15.06-1999 Robot Safety Standard An automatically controlled, reprogrammable multipurpose manipulator programmable in three or more axes which may be either fixed in place or mobile for use in industrial automation applications.

Merriam-Webster Online Dictionary
  A machine that looks like a human being and performs various complex acts (as walking or talking) of a human being.
  A device that automatically performs complicated often repetitive tasks.
  A mechanism guided by automatic controls
  An efficient insensitive person who functions automatically.

Britannica Encyclopedia. Any automatically operated machine that replaces human effort, though it may not look much like a human being or function in a humanlike manner.

Answers.com
  A mechanical device that sometimes resembles a human and is capable of performing a variety of often complex human tasks on command or by being programmed in advance.
  A machine or device that operates automatically or by remote control.
  A person who works mechanically without original thought, especially one who responds automatically to the commands of others.

webopedia.com
  A device that responds to sensory input.
  A program that runs automatically without human intervention. Typically, a robot is endowed with some artificial intelligence so that it can react to different situations it may encounter.