The term 'officially prohibit' can be expressed in three different ways: ENJOIN (6 letters), BAN (3 letters), and DEBAR (5 letters). ENJOIN means to order or command someone to do something, while BAN means to forbid or prohibit something. DEBAR is a more formal way of saying BAN, and it means to exclude someone from a certain activity or place. All three terms mean to officially prohibit something, either by ordering someone to do something, forbidding something, or excluding someone from something.