WordNet (r) 3.0 (2006):

teraflop
    n 1: (computer science) a unit for measuring the speed of a
         computer system [syn: teraflop, trillion floating point
         operations per second]

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

teraflop

    10^12 flops.

   Intel beat Hitachi to the record of 1.06 teraflops, on 04 Dec
   1996, unofficially in Beverton, Oregon, using 7264 Pentium
   Pro chips.

   (1997-07-21)