In zoology, a small invertebral animal, breathing by lateral spiracles, and furnished with articulated extremities and movable antennae. Most insects pass through three’ states or metamorphoses, the larva, the chrysalis, and the perfect insect. The class of insects, in the Linnean system, is divided into seven orders, the last of which includes the Crustacea, which breathe by gills, and the Arachnids, which have no antennae, now forming two distinct classes. The term insect has been applied, but improperly, to other small invertebral animals of the Linnean class Vermes.

Any thing small or contemptible.

Small; mean; contemptible.