crescent spanner

Meanings

1. An open-end adjustable spanner with a worm-drive thumbwheel. When the term adjustable spanner or adjustable wrench is used, this type (branded with any of many brands) is usually the type meant.
2. Used other than figuratively or idiomatically: any spanner made by the namesake company, which makes many tools.

1. Alternative letter-case form of crescent spanner.

Etymology

A genericization of the trade name of a company famous for making them (although it did not invent them); details are at Wikipedia. The trademark is still protected, and this genericized term is only informal and loose. Compare kleenex and coke.