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

Thread Language Zero
TL0

    (TL0) The instruction set of the TAM (Threaded
   Abstract Machine), used to implement Id.

   ["Fine-grain Parallelism with Minimal Hardware Support", David
   Culler et al, SIGPLAN Notices 26(4):164-175, ASPLOS-IV Proc,
   Apr 1991].

   (1995-03-13)