1. Tall European annual with downy grey-green foliage and dense heads of small white flowers followed by hairy pods; naturalized in North America, sometimes a troublesome weed
   "hoary alison spread rapidly through the untended field";
   - hoary alyssum, Berteroa incana

Type of: herb, herbaceous plant

Part of: Berteroa, genus Berteroa

Encyclopedia: Hoary alison