The noun forms of the verb to forbid are forbidder, forbiddance, and the gerund, forbidding.

Ban, forbiddance, exclusion, prevention, restriction, or veto. Those words mean prohibition.

Sanction, injunction, ban, boycott, writ, punitive measure, forbiddance, restriction, suspension, prohibition...

Censorship is a noun that means forbiddance or ban. One way the government uses censorship is by redacting certain information when they declassify files that were previously considered top secret.

A ban can refer to a prohibition or disallowance to do something, a forbiddance, or, in an obsolete sense, a curse or anathema against something.