glass tty

/glas T·T·Y/, /glas ti´tee/, n.

[obs.] 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. See * TV Typewriters* (Appendix A) for an interesting true story about a glass tty.