Maximum size is represented by Hippopotamus, which weighs up to 4,500 kg, and Giraffa, which attains a height of up to 5.8 meters. The main axis of the foot passes between the third and fourth digits, and the body weight is borne thereon. The humerus is usually shorter than the forearm, there being some few exceptions, and the radius and ulna are separated or fused. The ankle bone, or astragalus, has a rolling surface above the joint and a pulley surface below, giving free movement to the ankle. The fibula articulates with the heel bone, is usually slender or incomplete, and in some cases is fused with the tibia.
Many species have frontal appendages, commonly called horns or antlers.
The nasal bones are not expanded posteriorly as they are in the order Perissodactyla. There is no alisphenoid canal. The upper incisor teeth are reduced or absent. The canines usually are reduced or lost, though in some species they are enlarged and tusklike. They swallow the food rapidly, with little chewing, and then may retire to some secluded spot to digest it more thoroughly.