A methodology is usually a guideline system for solving a problem, with specific components such as phases, tasks, methods, techniques and tools.
(Retrieved from http://en.wikipedia.org/wiki/Methodology , 2013-01-24)
In the ux-field this term refers to different approaches to testing, developing, improving and analyzing user experience.
Questions with this tag deal with different methods used in UX, comparing or refining such methods or asking for categorization of a method.