<processor> One of Intel's Intel 486 family of microprocessors (one of the last before the Pentium). The 486DX has a working built-in floating point unit (FPU). The Intel 486SX is effectively a DX with the FPU disabled. The DX has a pin to select the external data bus width (16 or 32).
The Intel 487SX is a 486DX with a 486SX pinout.
Try this search on Wikipedia, OneLook, Google
Nearby terms: Intel 4004 « Intel 4040 « Intel 486 « Intel 486DX » Intel 486SX » Intel 487SX » Intel 8008