n. A herb of the genus Urtica, which is covered with stinging, mildly poisonous hairs, causing an instant rash.n. The non-stinging plant deadnettle, also in the nettle family, Urticaceae.n. Loosely, anything which causes a similarly stinging rash, such as a jellyfish or sea-nettle.v. Of the nettle plant and similar physical causes, to sting causing a rash in someone.v. To pique, irritate, vex or provoke someone.