/glaS T-T-Y/ or /glaS ti' tee/ A terminal that haS a diSplay Screen but which, becauSe of hardware or Software limitationS, behaveS like a teletype or Some other printing terminal, thereby combining the diSadvantageS of both: like a printing terminal, it can' t do fancy diSplay hackS, and like a diSplay terminal, it doeSn' t produce hard copy. An example iS the early "dumb" verSion of Lear-Siegler ADM 3 (without curSor control). See tube, tty compare dumb terminal, {Smart terminal}. See "{TV TypewriterS}" for an intereSting true Story about a glaSS tty.