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REFERENCE

signal

n. · v. · adj.
US //ˈsɪɡnəɫ// UK //sˈɪɡnəl// sig·nal
  1. 1 a sign or instruction (n.)
    B1 Intermediate

    a sound, action, or light that gives a message or a command.

    a sign, gesture, or device used to convey information, give notice of an occurrence, or initiate a concerted action.

    Example

    The referee gave the signal for the game to begin.

    Example

    The flare served as a prearranged signal for the ground troops to commence their advance toward the perimeter.
  2. 2 electronic transmission (n.)
    B1 Intermediate Computing

    the electronic waves that carry information to your phone, TV, or radio.

    an electromagnetic impulse or variable voltage that transmits data, audio, or video across a communication channel.

    Example

    I'm sorry, I can't hear you because my phone signal is very weak here.

    Example

    Engineers worked to filter out the background noise to ensure the satellite signal remained clear during the atmospheric disturbance.
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  1. 3 traffic light (n.)
    B1 Intermediate

    a light used to direct traffic on a road or railway.

    a technical device, such as a semaphore or light, used to regulate the movement of vehicles or trains.

    Example

    The driver stopped because the signal turned red.

    Example

    The automated railway signal failed during the storm, forcing all incoming trains to halt outside the station for safety.
  2. 4 to give a sign (v.)
    B1 Intermediate

    to show or tell something by making a movement or using a light.

    to communicate or indicate information through a non-verbal sign or electronic transmission.

    Example

    She signalled to the waiter that she wanted the bill.

    Example

    The CEO's speech was intended to signal a shift in the company's long-term environmental strategy to the shareholders.
  3. 5 notable or important (adj.)
    C2 Proficiency Formal Literary

    very important or easy to notice.

    distinguished from others by being particularly important, notable, or significant.

    Example

    The new law was a signal victory for the rights of workers.

    Example

    The signing of the peace treaty was regarded as a signal achievement in the diplomat's long and distinguished career.
Origin

From Old French segnal, seignal or Medieval Latin signāle; noun use of the neuter of Late Latin signālis, from Latin signum; verb use from 1805, as a shortened from signalize (1650s).

Idioms1 entry

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