| Waste minimization | (Environmental Engineering) The elimination or reduction of a waste prior to its generation. This is accomplished by process changes rather than waste treatment methods. |
| Wastewater | (Environmental Engineering) Consumed or used water from a municipality or industry that contains dissolved and/or suspended matter. |
| Weak acid | (Environmental Engineering) An acid that does not ionize completely under the conditions of interest. Examples include acetic acid, carbonic acid, and hypochlorous acid. See strong acid. |
| Wetland | (Environmental Engineering) Semi-aquatic land, that is land that is either inundated or saturated by water for varying periods of time during each year, and that supports aquatic vegetation which is specifically adapted for saturated soil conditions. |
| Adaptive maintenance - | (Software Engineering) activity associate with changing an application to make it conform to changes in its external environment |
| 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 |
| Beta testing - | (Software Engineering) testing that is conducted by the user |