In knot theory, a branch of mathematics, a knot or link K {\displaystyle K} in the 3-dimensional sphere S 3 {\displaystyle S^{3}} is called fibered or fibred if there is a 1-parameter family F t {\displaystyle F_{t}} of Seifert surfaces for K {\displaystyle K}, where the parameter t {\displaystyle t} runs through the points of the unit circle S 1 {\displaystyle S^{1}}, such that if s {\displaystyle s} is not equal to t {\displaystyle t} then the intersection of F s {\displaystyle F_{s}} and F t {\displaystyle F_{t}} is exactly K {\displaystyle K}. Wikipedia