plectoneme

This term is used almost exclusively within the specialized fields of molecular biology and biochemistry to describe the physical topology of DNA. It refers to the specific geometry where a double helix twists upon itself to form a coiled-coil structure, typically as a result of torsional stress or supercoiling.

Because it describes a precise structural configuration, it is rarely used in general conversation and is typically found in academic papers or textbooks discussing genomic architecture and enzyme activity, such as the action of topoisomerases.