monkey-wrench

verb (used with object)

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

verb (used without object)

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

noun

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

noun

1. a wrench with adjustable jaws