RhymeZone: auth definitions

Definitions of auth:

verb: (informal, computing) To authenticate.
noun: A surname.
noun: Abbreviation of authentication. [something which validates or confirms the authenticity of something]
noun: Abbreviation of authorization. [(uncountable) Permission.]
noun: Abbreviation of authoritarian. [One who commands absolute obedience to his or her authority.]

(Definitions from Wiktionary)