| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
voiceprint
police technique for identifying individuals by the time, frequency, and intensity of their speech-sound waves. A sound spectrograph is employed to record these waves in the form of a graph that may be compared to graphs of other individuals and differentiated. Though voice graphs (or voiceprints) have been used in courtroom proceedings, the accuracy of this technique in identifying individuals is a subject of controversy among speech scientists.
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