1. European annual wild lettuce having prickly stems; a troublesome weed in parts of United States
   - prickly lettuce, horse thistle, Lactuca serriola

Type of: compass flower, compass plant

• Rostov na Donu
• Rostov on Don
• rostral
• rostrate
• rostrum
• Roswell
• rosy
• rosy boa
• rosy-cheeked
• rosy-colored
• rosy-coloured
• rosy-purple
• rot
• rot-resistant
• rota
• Rotarian
• rotary
• rotary actuator
• Rotary Club
• rotary converter
• rotary engine
• Rotary International
• rotary joint
• rotary motion
• rotary press