micrometre

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.

noun

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

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

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

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.

1. A unit of length in the metric system equal to one millionth (10-6) of a meter. Also called micron