DVBST was an acronym used by Tektronix to describe their line of "Direct-View Bistable Storage Tubes". These were cathode ray tubes (CRTs) that stored information written to them using an analog technique inherent in the CRT and based upon the secondary emission of electrons. (See the discussion of "Analogue Storage" in the oscilloscope article.)
DVBSTs were used for analog oscilloscopes (such as the 603 monitor, the 611 monitor, and the 7623 plug-in mainframe oscilloscope) and for computer terminals such as the architypal Tek 4010 (the "mean green flashin' machine") and its several successors including the Tektronix 4014. Portions of the screen are individually written-to by a conventional electron beam, but erasure required erasing the entire screen in a bright flash of green light, leading to the nickname.
Some DVBST implementations also allowed the "write-through" of a small amount of dynamically refreshed, non-stored data. This allowed the display of cursors, graphic elements under construction, and the like on computer terminals.