1 Hydrogen is the most abundant element in the universe. 2  Hydrogen isn't common in a pure form on Earth, but is mostly found as part of water. 3  Hydrogen is the main fuel of stars and the only fuel for red dwarfs. 4  The whole universe is thought to have been formed by a Hydrogen nucleus.
Noun. 1. hindlimb-a posterior appendage such as a leg or the homologous structure in other animals. hind limb. hind leg-the back limb of a quadruped. limb-one of the jointed appendages of an animal used for locomotion or grasping: arm; leg; wing; flipper. 1  Facebook.
Hemivertebrae are a congenital deformity whereby parts of the vertebrae do not develop correctly, resulting in wedge shapes. As these wedged vertebrae line up, the spine may form one of three conditions: lordosis, a curvature in the lower back; kyphosis, a posterior curvature; or scoliosis, a lateral curvature. In many breeds, such as pugs, hemivertebrae development is encouraged, as it is responsible for the screw tail.