1. in a wicked, evil, or morally bad manner
2. in a dirty, filthy, or unpleasant manner
3. in a way that violates rules or fair play; unfairly
Usage: sports

Examples

• The villain foully murdered his rival in the dead of night.
• The water was foully contaminated and unsafe to drink.
• He was accused of foully fouling the opposing player during the match.
• The air smelled foully of rotting garbage.
• She spoke foully of her enemies without any restraint.
• The referee called a foul for foully tackling the quarterback.