To disallow; to proscribe.
Example: "Smoking in the restaurant is forbidden."
(ditransitive) to deny, exclude from, or warn off, by express command.
To oppose, hinder, or prevent, as if by an effectual command.
Example: "An impassable river forbids the approach of the army."
To accurse; to blast.
To defy; to challenge.
Example: "What part of "no" do you forbid to understand?"