/don' gl disk/ (Or "key disk") A kind of dongle consisting of a special floppy disk that is required in order to perform some task. Some contain special coding that allows an application to identify it uniquely, others *are* special code that does something that normally-resident programs don' t or can' t. For example, AT&T' s "Unix PC" would only come up in {root mode} with a special boot disk. [JarGon File] (1998-12-13)