WordNet (r) 3.0 (2006):

erasable programmable read-only memory
    n 1: (computer science) a read-only memory chip that can be
         erased by ultraviolet light and programmed again with new
         data [syn: erasable programmable read-only memory,
         EPROM]

The Free On-line Dictionary of Computing (30 December 2018):

Erasable Programmable Read-Only Memory
EPROM

    (EPROM) A type of storage device in which the data
   is determined by electrical charge stored in an isolated
   ("floating") MOS transistor gate.  The isolation is good
   enough to retain the charge almost indefinitely (more than ten
   years) without an external power supply.  The EPROM is
   programmed by "injecting" charge into the floating gate, using
   a technique based on the tunnel effect.  This requires higher
   voltage than in normal operation (usually 12V - 25V).  The
   floating gate can be discharged by applying ultraviolet light
   to the chip's surface through a quartz window in the package,
   erasing the memory contents and allowing the chip to be
   reprogrammed.

   (1995-04-22)