It is a Latin word meaning nettle, which itches or produces sting. Urtica is the name of a botanical genus of plants belonging to the family Urticaceae. They are characterized by being hives so they have hairs that sting, produce stinging when touched.
Urtica : Gender of urticaceous plants, annual or perennial herbs of opposite leaves, covered, the same as their stems, urticating hairs, tyremeraus and unisexual flowers, and dried fruit. They are called vulgarly ortigas.