Wasp (wŏsp), any one of a considerable group of insects, forming, with bees and ants, the highest order of insects (Hymenoptera). These well-known insects show some variation in form. Sometimes the thorax and abdomen are connected by a slender thread; but in other forms these parts of the body merge into one another. The social wasps, like the hornet or yellow jacket, are the best known. They build nests of paper attached to bushes, trees, roofs and eaves of buildings; or near the ground; or sometimes under stumps and stones. The paper is manufactured from wood-fiber obtained from posts and unpainted boards. This is chewed in the jaws and united into sheets, often of considerable extent. The nests are often top-shaped or balloon-shaped, with layers of cello inside resembling honeycomb, all inclosed in a spherical envelop of paper with a hole at the bottom for entrance and exit. The cells are hexagonal and in a single layer. In each cell one egg is placed; the larvae, on emerging, hang head downward. The nests in tropical countries sometimes are six feet long. The species of social wasps that make nests in the ground form a more fragile sort of paper from decayed wood. The colonies include three forms: males, females and workers. The males and workers die on the arrival of cold weather but the females live over the winter in sheltered places, and start a new colony in the spring. The workers only have stings. The solitary wasps include miners, mud-daubers and carpenters. The mason-wasps or mud-daubers are the most familiar, as their mud nests are commonly seen on beams and walls. The carpenters cut tubular nests in wood and divide them by mud partitions. The miners dig tunnels in the earth. Young wasps as a rule are fed largely on insects, though fruit and flower juices are included in their diet. Caterpillars, other larvae, grubs and spiders are stored away for future use. In all their work and habits wasps are of much interest. Consult Lubbock's Ants, Bees and Wasps and Howard's The Insect-Book. See Hornets.