verb (v)

• act in an official capacity in a ceremony or religious ritual, such as a wedding(verb.social)

  Example:
  Who officiated at your wedding?.
  

  source: wordnet30
• perform duties attached to a particular office or place or function(verb.competition)

  Example:
  His wife officiated as his private secretary.
  

  Synonym:
  function
  

  source: wordnet30
• To act as an officer in performing a duty; to transact the business of an office or public trust; to conduct a public service.(verb)

  source: webster1913
• To discharge, perform, or supply, as an official duty or function.(verb)

  source: webster1913