What does "countermand" mean?

Countermand: To prohibit; to forbid. [Obs.] Avicen countermands letting blood in choleric bodles. Harvey.

Additional senses

  1. 2.To oppose; to revoke the command of. For us to alter anuthing, is to lift ourselves against God; and, as it were, to countermand him. Hooker.
  2. 3.A contrary order; revocation of a former order or command. Have you no countermand for Claudio yet, But he must die to-morrow Shak.

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