knotwork

This term refers specifically to a stylized form of ornamentation where lines weave over and under one another without a visible beginning or end. It carries a strong association with early medieval art, particularly the Insular style of Ireland and Britain, as well as Scandinavian Viking art. Because it describes a specific artistic technique, it is used primarily in art history, archaeology, and craft contexts.

Grammatically, the word functions as a mass noun. It describes the overall style or the collective presence of these patterns on an object rather than individual knots. Consequently, it is rarely used in the plural form, as one would refer to a "piece of knotwork" or "intricate knotwork" rather than "knotworks."