| Object-oriented design (OOD) - | (Software Engineering) a technique for translating the OOA model into an implementation model |
| Objects - | (Software Engineering) a named element of the problem domain containing data and processing |
| OCL (Object Constraint Language) - | (Software Engineering) a supplement to UML, this formal language allows a software engineer to construct unambiguous statements about the characteristics of various design model elements |
| Outsourcing - | (Software Engineering) contracting software work to a third party |
| Pair programming - | (Software Engineering) two people work together (side-by-side) to design and construct a software component, providing real-time problem solving and quality control. |
| Paper prototype - | (Software Engineering) a paper representation of an application (e.g., story boards that describe the interaction at a human interface) |
| Paradigms - | (Software Engineering) the process model |
| Patterns - | (Software Engineering) a stylized description or characterization of a software problem or capability and/or the manner in which a solution to the problem or capability may be characterized, applied, and implemented |
| PDL - | (Software Engineering) program design language; a combination of natural language with programming language-like constructs |
| Perfective maintenance - | (Software Engineering) enhancement, |