| Noun | 1.prairie rocket - any of several North American plants of the genus Erysimum having large yellow flowersflower - a plant cultivated for its blooms or blossomsErysimum, genus Erysimum - large genus of annual or perennial herbs some grown for their flowers and some for their attractive evergreen leaves; Old World and North America | | 2.prairie rocket - any of several western American plants of the genus Cheiranthus having large yellow flowersflower - a plant cultivated for its blooms or blossomsCheiranthus, genus Cheiranthus - Old World perennial plants grown for their showy flowers |