[ ruhn-out ]
/ ˈrʌnˌaʊt /
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  1. the gradual termination of a groove on the body of an object not ending there, as the upper termination of a flute in a twist drill.
  2. Also called back clearance. a space in a depressed area of an object into which a machine tool or grinding wheel may safely enter at the end of a pass or operation.
the merging of a curved surface into another surface.
an act or instance of running away so as to evade, abandon, or avoid something.
a person who runs away so as to avoid payment or duty.
an act or instance of expiring or becoming depleted: the runout of a union contract; a runout in office supplies.
uneven wear on the outer edges of a tire or on the rim of a wheel.
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Origin of runout

First recorded in 1925–30; noun use of verb phrase run out

Other definitions for runout (2 of 2)

[ ruhn-out ]
/ ˈrʌnˌaʊt /

noun Manège.
the act of evading a jump or jumping outside of the limiting markers.

Origin of run-out

First recorded in 1865–70; noun use of verb phrase run out
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use runout in a sentence

British Dictionary definitions for runout

run out

verb (adverb)
(intr often foll by of) to exhaust (a supply of something) or (of a supply) to become exhausted
(intr) to expire; become no longer validmy passport has run out
run out on informal to desert or abandon
(tr) cricket to dismiss (a running batsman) by breaking the wicket with the ball, or with the ball in the hand, while he is out of his ground
noun run-out
cricket dismissal of a batsman by running him out
mechanical engineering an imperfection of a rotating component so that not all parts revolve about their intended axes relative to each other
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

Other Idioms and Phrases with runout

run out


Become used up or exhausted, as in Our supplies have run out. [Late 1600s]


Compel to leave; see run off, def. 5.


Become void, expire, as in Our renter's insurance ran out last month. [c. 1300] Also see run out of; run out on.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.