A skinfold is a type of measurement used to assess body fat levels. It involves pinching the skin on various parts of the body, such as the abdomen or thighs, and then using calipers to measure the thickness of the folded skin. This method provides an estimate of the individual's subcutaneous adipose tissue (SAT) which is a type of fat found just beneath the skin. Skinfold measurements are often used in combination with other methods, such as bioelectrical impedance or underwater weighing, to provide a more accurate assessment of body composition.