What specifically does “Melee Weapon Attack” mean?

@JeremyECrawford What specifically does "Melee Weapon Attack" mean: A melee attack with a weapon, or an attack with a melee weapon?

— Anonymous (@ApocalypticTwit) August 20, 2015

A melee weapon attack is a melee attack with a weapon. https://t.co/2OYgN4Ghgo

— Jeremy Crawford (@JeremyECrawford) August 20, 2015

@undrhil @ApocalypticTwitsince unarmed strikes are no longer considered weapons, they cannot be used for melee weapon attacks? The rule on unarmed strikes is an exception: they can be used for melee weapon attacks, despite not being weapons.

— Jeremy Crawford (@JeremyECrawford) August 20, 2015

@sebkhaNot to be confused with: an attack with a melee weapon.
That's correct, since an attack with a melee weapon can be a ranged attack if you throw it.

— Jeremy Crawford (@JeremyECrawford) August 20, 2015