Competency is Generic task or a function. The ability to put skills, knowledge and attitudes into practice in order to perform activities or a job in an effective and efficient manner within an occupation or job position to identified standards.
Expand the definition with a couple of sentences
The IAEA publication  defines competency as groups of related knowledge, skills and attitudes (KSAs) needed by a person to perform a particular job.
Competency represents the part of an individual's knowledge, skills and attitudes which can be observed and evaluated. The concept represent a HRM based view on managing knowledge.
Relation to KM
Explain why the term competency is relevant for KM