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

Tangible User Interface

    An attempt to give physical form to digital
   information, making bits directly manipulable and perceptible
   by people.  Tangible Interfaces will make bits accessible
   through augmented physical surfaces (e.g. walls, desktops,
   ceilings, windows), graspable objects (e.g. building blocks,
   models, instruments) and ambient media (e.g. light, sound,
   airflow, water-flow, kinetic sculpture) within physical
   environments.

   MIT Tangible Media Group (http://tangible.media.mit.edu/).

   (2003-10-17)