A wrench is a hand tool designed to grip and turn nuts, bolts, and pipes. Picture trying to tighten a bolt with just your fingers: it barely budges. But slip a wrench over that bolt's hexagonal head, and suddenly you have the leverage to turn it easily. The tool's long handle multiplies your force, letting you tighten or loosen fasteners that would otherwise be impossible to move.

Wrenches come in many varieties. An adjustable wrench has a movable jaw that slides to fit different sizes. A socket wrench uses interchangeable socket pieces that fit over bolt heads. Plumbers use specialized pipe wrenches with serrated jaws that grip round pipes tightly.

The word also means to pull or twist something violently. You might wrench open a stuck drawer, or wrench your ankle by twisting it awkwardly during soccer practice. When something is emotionally painful, we say it wrenches your heart: hearing about a friend moving away might give you a wrenching feeling in your chest.

The phrase “throw a wrench in the works” means to disrupt a plan suddenly, like when a thunderstorm throws a wrench into your outdoor party plans.