World Wide Words: Church key". World Wide Words. Archived from the original on 29 August 2018 . Retrieved 13 April 2016.

The word can also be used in slang to describe an unexpected obstacle, for example, "He threw a spanner in the works" (in U.S. English, "monkey wrench").

In North American English, wrench is the standard term. The most common shapes are called open-end wrench and box-end wrench. In American English, spanner refers to a specialized wrench with a series of pins or tabs around the circumference. (These pins or tabs fit into the holes or notches cut into the object to be turned.) In American commerce, such a wrench may be called a spanner wrench to distinguish it from the British sense of spanner. A wrench with one or several pins or hooks, designed to drive spanner head screws, threaded collars and retainer rings, shafts, and so on. Note the difference in the American and British senses of the word "spanner". In American English, "spanners" are a subset of the class of tools called "wrenches". A compact spanner for multiple sizes, historically used as a cheap DIY tool for bicycles when they used nuts or bolts, rather than the more modern allen bolt fittings

A tool that is similar in design and appearance to a monkey wrench, but with self-tightening properties and hardened, serrated jaws that securely grip soft iron pipe and pipe fittings. Sometimes known by the original patent holder's brand name as a "Stillson wrench" or a "Stilly".When re-fitting a wheel, the nuts (or bolts) should be tightened in a criss-cross pattern (to even out the forces) and initially should only be tightened "finger tight" on all nuts. In this context "finger tight" is tight enough to reach the point where free play is taken up and proper tightening is about to begin, say, the tightening force using the lug wrench/wheel brace like a screwdriver. This should be repeated twice, to ensure the wheel is properly centered and restrained by all nuts (as often the first nut that is tightened will be slightly loose after completing the set for the first time), then the wheel should be lowered to the ground and the criss-cross tightening pattern repeated to modest torque (say few fingers force on the lug wrench/wheel brace arm), and then finally repeated to full hand force.

spanner (n.)". Online Etymology Dictionary. Archived from the original on 17 November 2019 . Retrieved 17 November 2019.A flat wrench with a circular hole and two inward protruding pins to engage slots in the nut. This type of nut is used on bicycles to secure the front fork pivot bearing to the headpiece of the frame.