Competence (or competency) is the ability of an individual to do a job properly. A competency is a set of defined behaviors that provide a structured guide enabling the identification, evaluation and development of the behaviors in individual employees.
Regardless of training, competency would grow through experience and the extent of an individual to learn and adapt.
http://en.wikipedia.org/wiki/Competence_(human_resources)
http://www.infoq.com/interviews/agile2013-lacey