verb (used with object)

to ruin (plans, a schedule, etc.) unavoidably or, sometimes, deliberately: The storm monkey-wrenched our plans for a picnic.

verb (used without object)

to prevent, delay, or sabotage industrialization or development of wilderness areas, especially through vandalism.

Related formsmon·key-wrench·er, noun

monkey wrench


Also called, especially British, adjustable spanner. a wrench having an adjustable jaw permitting it to grasp nuts or the like of different sizes.
something that interferes with functioning; obstacle: He threw a monkey wrench into our plans.

Origin of monkey wrench

First recorded in 1855–60 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for monkey-wrench


Examples from the Web for monkey-wrench

Historical Examples of monkey-wrench

  • David threw down the monkey-wrench, and put an arm about her waist.

    Tiverton Tales

    Alice Brown

  • Only minutes had gone by since the blows from the monkey-wrench.

    Raiders Invisible

    Desmond Winter Hall

  • When I told her about the monkey-wrench and the lemon pie, she was just as much puzzled as I was.

    Just Patty

    Jean Webster

  • "I'll get a monkey-wrench, my friend; you rattle," Brent chuckled.

    Sunlight Patch

    Credo Fitch Harris

  • He went below with a monkey-wrench, unscrewed the nut, and let the hook drop off.

British Dictionary definitions for monkey-wrench

monkey wrench


a wrench with adjustable jaws
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