/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.