(in sport) an unfair or invalid stroke or piece of play, especially one involving interference with an opponent

the midfielder was booked for a foul on Ford

a disease in the feet of cattle

he was indeed suffering from foul of the foot

make foul or dirty; pollute

factories which fouled the atmosphere

(in sport) commit a foul against (an opponent)

United claim their keeper was fouled

collide with or obstruct

the ships became overcrowded and fouled each other

will have to work towards solutions to prevent trucks from fouling railroad tracks