[1] : The Collaborative International Dictionary of English v.0.48

officiate \offi"ciate\, v. i. imp.  p. p. officiated; p.
   pr.  vb. n. officiating. ll. officiare. see office.
   to act as an officer in performing a duty; to transact the
   business of an office or public trust; to conduct a public
   ceremony or service. --bp. stillingfleet.
   1913 webster
see also:
officiated officiating office 

[2] : The Collaborative International Dictionary of English v.0.48

officiate \offi"ciate\, v. t.
   to discharge, perform, or supply, as an official duty or
   function. obs.
   1913 webster

         merely to officiate light
         round this opacous earth.                --milton.
   1913 webster

[3] : WordNet (r) 2.0

officiate
     v 1: act in an official capacity in a ceremony or religious
          ritual, such as a wedding; "who officiated at your
          wedding?"
     2: perform duties attached to a particular office or place or
        function; "his wife officiated as his private secretary"
        syn: function
see also:
function 

[4] : Moby Thesaurus II by Grady Ward, 1.0

43 moby thesaurus words for "officiate":
   act, act as, adjudicate, administer, administer the eucharist,
   administrate, anoint, arbitrate, chair, chairman, chrism, conduct,
   confirm, direct, do duty, function, head up, hear, hold court,
   hold the scales, impose, judge, lay hands on, lead, manage,
   mediate, minister, moderate, occupy the chair, oversee,
   perform a rite, perform as, perform service, preside, preside over,
   referee, run, serve, sit in judgment, superintend, supervise, try,
   umpire

Officiate >> O Words
Officiate, definition of term: Officiate
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