1. (Science: zoology) Any jumping, orthopterous insect, of the families Acrididae and Locustidae. The species and genera are very numerous. The former family includes the western grasshopper or locust (Caloptenus spretus), noted for the great extent of its ravages in the region beyond the Mississippi. In the Eastern united states the red-legged (Caloptenus femurrubrum and c. Atlanis) are closely related species, but their ravages are less important. They are closely related to the migratory locusts of the old world. See locust.
The meadow or green grasshoppers belong to the Locustidae. They have long antennae, large ovipositors, and stridulating organs at the base of the wings in the male. The European great green grasshopper (locusta viridissima) belongs to this family. The common American green species mostly belong to Xiphidium, Orchelimum, and Conocephalus.
2. In ordinary square or upright pianos of london make, the escapement lever or jack, so made that it can be taken out and replaced with the key; called also the hopper. Grasshopper engine, a steam engine having a working beam with its fulcrum at one end, the steam cylinder at the other end, and the connecting rod at an intermediate point.