| Trophic level | (Environmental Engineering) A level in the food chain. The first trophic level consists of the primary producers, autotrophs. The second trophic level is vegetarians which consume autotrophic organisms. |
| Ultimate disposal | (Environmental Engineering) The process of returning residuals back to the environment in a form which will have the minimal or reduced negative environmental impacts. |
| Abstraction - | (Software Engineering) (1) the level of technical detail of some representation of software; (2) a cohesive model of data or an algorithmic procedureAction (also called Software engineering action) - |
| Aesthetic design - | (Software Engineering) a Web engineering action that focuses on the aesthetics (e.g., the artistic elements) of a WebApp (often encompasses graphic design) |
| Agile development (also referred to as agile process model) - | (Software Engineering) an adapted version of software engineering that emphasizes customer communication, incremental software delivery, informal methods and work products, and highly motivated teams. |
| Analysis - | (Software Engineering) a set of activities that attempt to understand and model customer needs and constraintsAnalysis methods - |
| Architectural design - | an activity that attempts to layout the module "floor plan" for the software |
| Aspect-oriented development - | (Software Engineering) a development approach that emphasizes "concerns" (also called "aspectual requirements" that incorporate features, functions and information content) that cut across multiple system functions |
| Basis path testing - | (Software Engineering) a white box test case design technique that used the algorithmic flow of the program to design tests |
| Basis set - | (Software Engineering) the set of tests derived using basis path testingBehavioral modeling - |