- a gesture, action, or sound that is used to convey information or instructions, typically by pre-arrangement between the parties concerned信号; 暗号：
the firing of the gun was the signal for a chain of beacons to be lit
开枪是接连点燃烽火的信号
with infinitive the policeman raised his hand as a signal to stop.警察举起手, 示意停下。
- an indication of a state of affairs标志; 表示：
the markets are waiting for a clear signal about the direction of policy.
市场正等待着一个明确的政策动向。
- an event or statement that provides the impulse or occasion for something specified to happen起因; 导火线：
the champion's announcement that he was retiring was the signal for scores of journalists to gather at his last match.
这位冠军宣布他将退役, 这就是那么多记者出席他最后一场比赛的原因。
- an apparatus on a railway, typically a coloured light or a semaphore, giving indications to train drivers of whether or not the line is clear（铁路上的）信号灯。
- Bridge a pre-arranged convention of bidding or play intended to convey information to one's partner【桥牌】信号。
- an electrical impulse or radio wave transmitted or received（电脉冲或无线电波传递或接收的）信号：
equipment for receiving TV signals.
接收电视信号的设备。
- transmit information or instructions by means of a gesture, action, or sound用信号传递信息（或指示）; 发信号：
hold your fire until I signal.
在我发信号之前, 一直举着火把。
- with obj. and infinitive instruct (someone) to do something by means of gestures or signs rather than explicit orders（用信号）示意：
she signalled Charlotte to be silent.
她示意夏洛特不要说话。
- (of a cyclist, motorist, or vehicle) indicate an intention to turn in a specified direction using an extended arm or flashing indicator（骑自行车者, 驾驶司机, 交通工具）打信号（以示转向）：
with complement Stone signalled right斯通打出右转的信号
with infinitive the truck signalled to turn left.卡车打出左转的信号。
- with obj. indicate the existence or occurrence of (something) by actions or sounds（用举动或声音）表示, 表明：
the Community could signal displeasure by refusing to cooperate.
该社区可以通过拒绝合作来表明自己的不悦。
- with clause give an indication of a state of affairs指示, 表明：
she gave a glance which signalled that her father was being secretive.
她瞥了一眼, 暗示她父亲不坦率。
signaller
noun- striking in extent, seriousness, or importance; outstanding明显的; 显著的; 显要的; 出色的：
he attacked the government for their signal failure of leadership.
他攻击政府明显领导无能。