The Free On-line Dictionary of Computing (30 December 2018):

traceroute

    A TCP/IP utility, originally Unix, which
   allows the user to determine the route packets are taking
   to a particular host.  Traceroute works by increasing the
   "time to live" value of packets and seeing how far they get,
   until they reach the given destination; thus, a lengthening
   trail of hosts passed through is built up.

   (2007-02-02)