1. According to need (physicians use PRN in writing prescriptions)
   - as needed, as required, PRN

Encyclopedia: Pro re nata

• fruitage
• fruitarian
• fruitcake
• fruiterer
• fruitful
• fruitfully
• fruitfulness
• fruitiness
• fruiting
• fruiting body
• fruition
• fruitless
• fruitlessly
• fruitlessness
• fruitlet
• fruitwood
• fruity
• frumenty
• frump
• frumpily
• frumpish
• frumpishly
• frumpy
• Frunze
• frustrate