stinkbug

noun

1. Any of several insects, usually shield-shaped, possessing a gland that produces a foul-smelling liquid, usually containing aldehydes which they use to discourage predators.
2. A common name applied to various insects of the Hemiptera order (the "true bugs"), in the Heteroptera suborder, principally in the superfamilies Pentatomoidea and Coreoidea.
3. (US Southwest) A pinacate beetle or stink beetle (genus Eleodes) that releases a pungent odor when threatened.