A foul is a rule infraction for which a penalty is prescribed.
A personal foul is a foul involving illegal physical contact that endangers the safety of another player.
Flagrant Personal Foul
A flagrant personal foul is illegal physical contact so extreme or deliberate that it places an opponent in danger of catastrophic injury.
A violation is a rule infraction for which no penalty is prescribed. Since it is not a foul, it does not offset a foul.