A wasp is any insect of the order Hymenoptera and suborder Apocrita that is not a bee, sawfly, or an ant. Less familiar, the suborder Symphyta includes the sawflies and wood wasps, which differ from the Apocrita by having a broad connection between the thorax and abdomen. Also, Symphyta larvae are mostly herbivorous and "caterpillarlike", whereas those of Apocrita are largely predatory or parasitic.

Wasps themselves do not take any nutrients from their prey. Indeed, adult wasps, much like bees, butterflies, and moths, derive all of their nutrition from nectar. Wasps paralyze their prey by injecting it with toxic venom through their stingers. They then inject the prey with eggs; when the eggs hatch, the larvae eat the prey alive, saving the vital organs for last. They pupate inside the prey's body, and upon becoming adults, cut a hole in the prey's skin and fly out. Wasps are probably the inspiration for the titular creatures of the Alien series. This form of predation is also seen in the Black Arms from the Sega video game Shadow the Hedgehog.

Every night Wasps bite into the stem of a plant, lock their mandibles into position, stretch out at right angles to the stem, and, with legs dangling and fall asleep.