the time taken from the onset of a stimulus to the completion of a task e.g. time between hearing the gun &  hitting the finish line
the time from the onset of a signal to repsond (stimulus) to the final completeuion of the response or action, i.e reaction time + movememnt time.
In an unusual move , the U.S. Patent and Trademark Office is reconsidering a patent affecting Internet pages that critics contend could disrupt millions of Web sites .