Form a knee is a phrase that refers to the architectural element found in houses and buildings. It is also used as a metaphor for a human leg joint that resembles the shape of the knee. Some synonyms for form a knee include generate a bend, create an angle, shape a joint, establish a crook, and develop a curve. When constructing or designing a structure with a gable roof, forming a knee is an essential feature to ensure that the roof remains stable and structurally sound. In human anatomy, the knee is a vital joint that connects the thigh bone and the shinbone, and it can also be easily injured if not well maintained.