credential
Pronunciation: /krɪˈdɛnʃ(ə)l/
noun
(usually credentials)- a qualification, achievement, quality, or aspect of a person’s background, especially when used to indicate their suitability for something: recruitment is based mainly on academic credentials
- a document proving a person’s identity or qualifications: examine carefully the credentials of all callers before admitting them
- a letter of introduction given by a government to an ambassador before a new posting: the Russian ambassador presented his credentials on September 30
verb

Origin:
late Middle English: from medieval Latin credentialis, from credentia (see credence). The original use was as an adjective in the sense 'giving credence to, recommending', frequently in credential letters or papers, hence credentials (mid 17th century)