1. A weedy perennial with tough wiry stems and purple flowers; native to Europe but widely naturalized
   - lesser knapweed, black knapweed, hardheads

Type of: knapweed

• Rutherford atom
• Rutherford B. Hayes
• Rutherford Birchard Hayes
• rutherfordium
• ruthful
• ruthfulness
• ruthless
• ruthlessly
• ruthlessness
• rutilant
• rutile
• Rutilus
• Rutilus rutilus
• rutin
• Rutland
• Rutledge
• rutted
• rutter
• ruttish
• rutty
• Ruvettus pretiosus
• RV
• Rwanda
• Rwanda franc
• Rwandan