English Reference
noun · verb · adjective

signal

n. · v. · adj.
US /ˈsɪɡnəɫ/ UK /sˈɪɡnəl/ sig·nal UK spelling signaled, signals

  1. 01 B1 Intermediate

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

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

    Simple

    The referee gave the signal for the game to begin.

    In context

    The flare served as a prearranged signal for the ground troops to commence their advance toward the perimeter.

  2. 02 B1 Intermediate Computing

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

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

    Simple

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

    In context

    Engineers worked to filter out the background noise to ensure the satellite signal remained clear during the atmospheric disturbance.

  3. 03 B1 Intermediate

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

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

    Simple

    The driver stopped because the signal turned red.

    In context

    The automated railway signal failed during the storm, forcing all incoming trains to halt outside the station for safety.

    traffic lightindicator
  4. 04 B1 Intermediate

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

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

    Simple

    She signalled to the waiter that she wanted the bill.

    In context

    The CEO's speech was intended to signal a shift in the company's long-term environmental strategy to the shareholders.

  5. 05 C2 Proficiency FormalLiterary

    adj.very important or easy to notice.

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

    Simple

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

    In context

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

Usage signal from the noise · send signal · signal a new


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).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin signum
Level B1 · Intermediate
Frequency Common
Updated