also: ファールライン
noun
foul line
Used in sports such as baseball, basketball, and bowling to refer to the boundary line that determines whether a ball or player is in foul territory or has committed a foul.
バスケットボールでは、フリースローを打つときにファウルラインを踏んではいけない。
In basketball, you must not step on the foul line when shooting a free throw.
野球のファウルラインの外側にボールが落ちた。
The ball fell outside the foul line in baseball.
Borrowed from English 'foul line'.