any of several species of a widely distributed plant with greenish flowers and jagged leaves covered with stinging hairs: Urtica dioica and other species

(used in combinations) any of various plants like the nettle

dead nettle

said of a remark, etc: to goad or sting (somebody)

Nettled by the criticism, she retaliated fiercely

to strike or sting (somebody) with or as if with nettles