Knuckle-like process at the end of a bone is called a condyle.
Condyle refers to a round prominence at the end of a bone, usually forming a joint between two bones. It can be found on the femur (in the knee joint), on the tibia (in the knee joint), on the humerus (in the elbow joint), on the mandible (in the temporomandibular joint), and on the occipital bone (in the atlanto-occipital joint).