micrometer

1
[mahy-krom-i-ter]
noun
  1. any of various devices for measuring minute distances, angles, etc., as in connection with a telescope or microscope.
  2. Also called mike. micrometer caliper. a precision instrument with a spindle moved by a finely threaded screw, for the measurement of thicknesses and short lengths, commonly used by machinists for turning shafts or boring holes.
Also especially British, mi·crom·e·tre.

Origin of micrometer

1
First recorded in 1660–70; micro- + -meter
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for micrometre

micrometre

noun
  1. a unit of length equal to 10 –6 metreSymbol: μm Former name: micron

micrometer

noun
  1. any of various instruments or devices for the accurate measurement of distances or angles
  2. Also called: micrometer gauge, micrometer calliper a type of gauge for the accurate measurement of small distances, thicknesses, diameters, etc. The gap between its measuring faces is adjusted by a fine screw, the rotation of the screw giving a sensitive measure of the distance moved by the face
Derived Formsmicrometry, nounmicrometric (ˌmaɪkrəʊˈmɛtrɪk) or micrometrical, adjective
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

Word Origin and History for micrometre

micrometer

n.

1660s, from micro- + -meter. Originally a telescope attachment; from 1884 as a craftsman's fine measuring tool. Related: Micrometry; micrometric.

Online Etymology Dictionary, © 2010 Douglas Harper

micrometre in Science

micrometer

1
[mī-krŏmĭ-tər]
  1. A device for measuring very small distances, angles, or objects, especially one based on the rotation of a finely threaded screw, as in relation to a microscope.

micrometer

2
[mīkrō-mē′tər]
  1. A unit of length in the metric system equal to one millionth (10-6) of a meter. Also called micron
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.