The referee showed a red card to the fouler.

He is fouler than I thought.

She bought several foulards to match her outfits.

I bought a beautiful foulé scarf.

He played foully and was given a red card.

He is known for his foulmouthed language.

The foulest smell filled the room.

The foulant on the surface of the pipe caused a decrease in flow rate.

The foulers were penalized for their aggressive play.

The beekeeper discovered foulbrood in one of the hives.