Heaviside layer/ʹhevisied/ noun

• rose of Sharon
• roseola
• rose-tinted
• rosette
• rose water
• rose window
• rosewood
• Rosh Hashanah
• Rosicrucian
• rosin
• RoSPA
• roster
• rostrum
• rosy
• rosé
• rot
• rota
• Rotarian
• rotary
• Rotary Club
• rotary press
• rotate
• rotation
• rotator
• rotavator