NOUN (1)

1. a spectator who can describe what happened;


VERB (1)

1. be present at an event and see it with one's own eyes;

The Collaborative International Dictionary of English v.0.48:

Eyewitness \Eye"wit`ness\, n.
   One who sees a thing done; one who has ocular view of
   anything.
   [1913 Webster]

         We . . . were eyewitnesses of his majesty. --2 Pet. i.
                                                  16.
   [1913 Webster]

WordNet (r) 3.0 (2006):

eyewitness
    n 1: a spectator who can describe what happened
    v 1: be present at an event and see it with one's own eyes

Moby Thesaurus II by Grady Ward, 1.0:

88 Moby Thesaurus words for "eyewitness":
   TV-viewer, absolute, adducible, admissible, attestant, attestative,
   attestator, attester, attestive, authentic, based on, beholder,
   bird-watcher, bystander, certain, circumstantial, cojuror,
   compurgator, conclusive, convincing, cumulative, damning, decisive,
   deponent, determinative, documentary, documented, drugstore cowboy,
   earwitness, evidential, evidentiary, ex parte, eye-witness,
   factual, final, firsthand, founded on, gaper, gazer, gazer-on,
   girl-watcher, goggler, grounded on, hearsay, implicit,
   incontrovertible, indicative, indisputable, informant, informer,
   irrefutable, irresistible, kibitzer, looker, looker-on, material,
   nuncupative, observer, ogler, onlooker, overwhelming, passerby,
   perceiver, percipient, presumptive, probative, reliable, seer,
   sidewalk superintendent, significant, spectator, spectatress,
   spectatrix, suggestive, sure, swearer, symptomatic, televiewer,
   television-viewer, telling, testifier, valid, video-gazer, viewer,
   voucher, watcher, weighty, witness



Bouvier's Law Dictionary, Revised 6th Ed (1856):

EYE-WITNESS. One who saw the act or fact to which he testifies. When an eye-
witness testifies, and is a man of intelligence and integrity, much reliance
must be placed on his testimony, for he has the means of making known the
truth.