A device for measuring very small distances, objects, or angles, especially one based on the rotation of a finely threaded screw, as in relation to a microscope.
A unit of length equal to one thousandth (10-3) of a millimeter or one millionth (10-6)of a meter.
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.