Connecting Credentials—Glossary of Credentialing Terminology (6/2016): Documented award by a responsible and authorized body that attests that an individual has achieved specific learning outcomes or attained a defined level of knowledge or skill relative to a given standard. Credential, in this context, is an umbrella term that includes degrees, diplomas, licenses, certificates, badges, and professional and industry certifications.
Goodwin: A credential is officially documented credit that verifies an individual’s qualification or competency in a specific skill. Credentials are earned and awarded by completing a course of study, successfully passing an assessment, or meeting specified requirements that verify competency.
Wikipedia: A piece of any document that details a qualification, competence, or authority issued to an individual by a third party with a relevant or de facto authority or assumed competence to do so. Examples of credentials include academic diplomas, academic degrees, certifications, security clearances, identification documents, badges, passwords, usernames, keys, powers of attorney, and so on. Sometimes publications, such as scientific papers or books, may be viewed as similar to credentials by some people, especially if the publication was peer-reviewed or made in a well-known journal or reputable publisher.