operation code 
noun Computing
The part of a machine code instruction that defines the operation to be performed.Send both numbers and the operation code to the execution unit.
- Horlivka
- hormesis
- hormonal
- hormonally
- hormonal replacement
- hormone
- hormone replacement
- hormone replacement therapy
- hormone therapy
- hormone treatment
- Hormuz
- Hormuz, Strait of
- horn
- hornbag
- hornbeam
- hornbill
- hornblende
- hornbook
- Horn, Cape
- horndog
- horned
- horned grebe
- horned lark
- horned lizard
- horned owl