The term 'ornamental spiral' can be described as a HELIX, which is a three-dimensional structure made up of a single continuous line that winds around a central axis. It is often used in architecture and art to create decorative patterns and shapes. Helices are also found in nature, such as in the structure of DNA molecules. Ornamental spirals are often used to decorate objects, buildings, and other structures, adding an aesthetically pleasing element to the design.