Definitions
1.VerbTo revoke (a former command); to cancel or rescind by giving an order contrary to one previously given."to countermand an order for goods"
2.VerbTo recall a person or unit with such an order.
3.VerbTo cancel an order for (some specified goods).
4.VerbTo counteract, to act against, to frustrate.
5.VerbTo prohibit (a course of action or behavior).
6.VerbTo oppose or revoke the command of (someone).
7.VerbTo maintain control of, to keep under command.
8.NounAn order to the contrary of a previous one.