Noun
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.
(entomology) Any of various insects of the Hemiptera order (the "true bugs"), in the Heteroptera suborder, principally in the superfamilies Pentatomoidea and Coreoidea.
(Southwestern US) A pinacate beetle or stink beetle (genus Eleodes) that releases a pungent odor when threatened.
Source: en.wiktionary.org