Source : WordNet®

RISC
     n : (computer science) a kind of computer architecture that has
         a relatively small set of computer instructions that it
         can perform [syn: {reduced instruction set computing}, {reduced
         instruction set computer}] [ant: {complex instruction set
         computing}, {complex instruction set computing}, {complex
         instruction set computing}]

Source : Free On-Line Dictionary of Computing

RISC
     
        {Reduced Instruction Set Computer}