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[uhl-truh-mahy-kruh-skohp] /ˌʌl trəˈmaɪ krəˌskoʊp/
an instrument that uses scattering phenomena to detect the position of objects too small to be seen by an ordinary microscope.
1905-10; ultra- + microscope
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[uhl-truh-mahy-kruh-skop-ik] /ˌʌl trəˌmaɪ krəˈskɒp ɪk/ (Show IPA),
ultramicroscopical, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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British Dictionary definitions for ultra-microscopic


a microscope used for studying colloids, in which the sample is strongly illuminated from the side and colloidal particles are seen as bright points on a dark background Also called dark-field microscope
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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ultra-microscopic in Medicine

ultramicroscope ul·tra·mi·cro·scope (ŭl'trə-mī'krə-skōp')
A microscope with high-intensity illumination used to study very minute objects.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Encyclopedia Article for ultra-microscopic


microscope arrangement used to study colloidal-size particles that are too small to be visible in an ordinary light microscope. The particles, usually suspended in a liquid, are illuminated with a strong light beam perpendicular to the optical axis of the microscope. These particles scatter light, and their movements are seen only as flashes against a dark background; their structure is not resolved.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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