Isoptera (termites, white ants; class Insecta, subclass Pterygota) Order of hemimetabolous insects, related to cockroaches, in which all species are social and polymorphic, with primary and secondary reproductives, soldiers, and workers. Nests (termitaria) may be cavities in the ground or wood, earth mounds, or carton constructions, Termites forage for plant material, using odour trails, and rely on gut-swelling, symbiotic micro-organisms (protozoa in lower termites, bacteria in Termitidae) for the digestion of cellulose. Anal trophallaxis distributes these symbionts, and pheromones involved in caste determination, among the colony members. There are about 2200 living species, most being restricted to the tropics.

Isoptera An order of social exopterygote insects that comprises the termites. These mainly tropical insects have a complex system of castes, including wingless workers and soldiers and primary and secondary winged reproductive members. A termite colony is founded by a single reproductive pair, the nest comprising an elaborate system of tunnels in wood or soil. Termites rely on gut microflora for cellulose digestion, causing considerable damage to wooden structures if they invade houses.

ter·mite / ˈtərˌmīt/ • n. a small, pale soft-bodied insect (order Isoptera) that lives in large colonies with several different castes, typically within a mound of cemented earth. Many kinds feed on wood and can be highly destructive to trees and timber. Also called white ant.

termite Social insect found worldwide in subterranean nests and above-ground mounds. They have a caste system, with a king and queen guarded and tended by soldiers, workers and nymphs. Wood is a common component of their diet, which is digested with the help of symbiotic protozoa or bacteria that live in the termites' intestines. Length: 0.2–2.25mm (0.08–0.9in); queens: to 10cm (4in). Order Isoptera.

termite XVIII. — late L. termes, termit- woodworm, alt. of tarmes woodworm (perh. by assim. to terere rub).