1. In a productive way
   - productively, profitably, prolifically

Antonym: fruitlessly

• butter cookie
• butter daisy
• butter dish
• butter knife
• butter tart
• butter up
• butter-and-eggs
• butter-bean plant
• butter-print
• butterball
• butterbean
• butterbur
• buttercrunch
• buttercup
• buttercup family
• buttercup squash
• butterfat
• Butterfield
• butterfingered
• butterfingers
• butterfish
• butterflower
• butterfly
• butterfly bush
• butterfly collector