[countable] an official rule that says that sth is not allowed禁止；禁令◆a ban on overtime/ on tobacco advertising禁止加班／刊登烟草广告◆Congress has been urged to impose a ban on all cloning research.人们一直敦促国会对所有克隆研究颁布禁令。⨁to impose / lift a ban颁布／解除禁令