A denier unit-of-measurement is used to determine the thickness or density of fabrics or fibers. Synonyms for this term include "denier number" or simply "denier." It is a metric commonly utilized in the textile industry to quantify the weight of yarn or thread. The higher the denier number, the denser and more durable the fabric tends to be. Additionally, this unit-of-measurement is often referred to as "tex" in the scientific community, particularly when measuring the linear mass density of fibers or strands. Overall, denier unit-of-measurement, denier number, and tex are interchangeable terms used to classify and describe the thickness or density of various materials in the textile and scientific fields.