DEDDark-Emitting Diode (that is, a burned-out LED). Compare SED, LER, write-only memory. In the early 1970s both Signetics and Texas instruments released DED spec sheets as AFJs (suggested uses included "as a power-off indicator"). [Jargon File]
DECwindows ♦ DECwrite ♦ DED ♦ dedicated line ♦ deductive database ♦ deductive tableau
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