- 1a curved structure that supports the weight of something above it, such as a bridge or the upper part of a building a bridge with three arches
- 2 a structure with a curved top that is supported by straight sides, sometimes forming an entrance or built as a monument Go through the arch and follow the path. The Gateway Arch is a famous St. Louis landmark.
- 3the raised part of the foot formed by a curved section of bones
- 4anything that forms a curved shape at the top the delicate arch of her eyebrows