A plant of the genus Urtica, covered with minute sharp hairs containing a poison that produces a stinging sensation. Urtica gracitis is common in the Northern, and U. chamædryoides in the Southern, United States. the common European species, U. urens and U. dioica, are also found in the Eastern united States. U. pilulifera is the Roman nettle of England.
- Any of numerous plants of the genus Urtica, having toothed leaves, unisexual apetalous flowers, and stinging hairs that cause skin irritation on contact.
- Any of various hairy, stinging, or prickly plants.
- To sting with or as if with a nettle.
- To irritate; vex.