From The Collaborative International Dictionary of English v.0.48 [gcide]:
hologram \hol"o*gram\, noun A photographic image giving the observer a seemingly three-dimensional view of the represented object. The three-dimensional effect is produced by exposing a photographic recording medium to an interference pattern generated by a coherent beam of light (as from a laser) reflected from the subject, interacting with a beam directly from the source. The full three-dimensional effect requires illumination of the image with coherent light, but less perfect three-dimensional visual effects may also be observed when the hologram is illuminated with white light. [PJC]
From WordNet (r) 3.0 (2006) [wn]:
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