Definition of "opcode"

opcode

noun
plural opcodes
1. (computing) A mnemonic used to refer to a microprocessor instruction in assembly language.
  Quotations
  When the microprocessor decodes the JSR opcode, it stores the operand into the TEMP register and pushes the current contents of the PC ($00 0128) onto the stack.
  1992, Michael A. Miller, The 68000 Microprocessor Family: Architecture, Programming, and Applications, page 47
  In the tradition of other low-level languages, many CIL opcodes tend to be cryptic and completely unpronounceable by us mere humans.
  2010, Andrew Troelsen, Pro C# 2010 and the .NET 4 Platform, page 655