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

field-programmable gate array

    (FPGA) A gate array where the logic network can
   be programmed into the device after its manufacture.  An FPGA
   consists of an array of logic elements, either gates or lookup
   table RAMs, flip-flops and programmable interconnect
   wiring.

   Most FPGAs are reprogrammable, since their logic functions and
   interconnect are defined by RAM cells.  The Xilinx LCA,
   Altera FLEX and AT&T ORCA devices are examples.  Others
   can only be programmed once, by closing "antifuses".  These
   retain their programming permanently.  The Actel FPGAs are
   the leading example of such devices.  Atmel FPGAs are
   currently (July 1997) the only ones in which part of the array
   can be reprogrammed while other parts are active.

   As of 1994, FPGAs have logic capacity up to 10K to 20K
   2-input-NAND-equivalent gates, up to about 200 I/O pins and
   can run at clock rates of 50 MHz or more.  FPGA designs must
   be prepared using CAD software tools, usually provided by
   the chip vendor, to do technology mapping, partitioning and
   placement, routing, and binary output.  The resulting binary
   can be programmed into a ROM connected to the FPGA or
   downloaded to the FPGA from a connected computer.

   In addition to ordinary logic applications, FPGAs have enabled
   the development of logic emulators.  There is also research
   on using FPGAs as computing devices, taking direct advantage
   of their reconfigurability into problem-specific hardware
   processors.

   Usenet newsgroup: news:comp.arch.fpga.

   (1997-07-11)