Gibbon (hylobates), a genus of apes, sometimes called wood-walkers from their astonishing agility in swinging from tree to tree. They seem to form a connecting link between the apes and the baboons, having in a small degree the posterior callosities of the latter. The arms are of enormous length, the chest capacious, the legs short, the hair soft, and the voice very loud. They rarely exceed 4 ft. in height, and many are under 3; the arms reach to the ground, and when extended are twice the length of the body. The white-handed gibbon (H lar) varies in color from black to brown, the hands being much lighter; it is an inhabitant of Malacca and Siam. The agile gibbon (H. agilis) and the silvery gibbon (H. leuciscvs), of the same countries, are nearly allied species, or perhaps mere varieties. The gibbons are the most active of the quadrumana in the trees, but very awkward on the ground; very shy in their native haunts, in captivity they are the most docile and gentle of the apes; they generally live in pairs.
One variety is sometimes called hoolock.