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.
The femur or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in the hindlimbs. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with the tibia and kneecap forming the knee join