Signal | Mean of signal in English Dictionary

/ˈsɪgnl̟/

• Noun
• an event or act which shows that something exists or that gives information about something
1. The change in his behavior is clearly a signal [=indication] that there is a problem.
2. He likes her but he is sending the wrong signals with his constant teasing.
3. Inflammation is a signal of infection.
• something (such as a sound, a movement of part of the body, or an object) that gives information about something or that tells someone to do something
1. Don't start until I give the signal. [=sign]
2. The teacher gave us the signal to finish what we were working on and hand in our tests.
3. The pilot sent out a distress signal [=a message that the airplane was in danger] before the plane crashed.
4. They communicated with each other by using hand signals. [=movements of a person's hands that mean something]
• a piece of equipment with colored lights that is used on railways and roads to tell people when to go, to slow down, or to stop
1. Faulty wiring in the train station caused a signal to malfunction.
2. The traffic signal [=traffic light] was not working.

• a message, sound, or image that is carried by waves of light or sound
1. The video/TV signal is scrambled.
2. Satellite dishes receive television signals.
3. a digital signal
4. The transmitter beams radio signals into space.
• a wave of light or sound that carries a message, sound, or image
1. We'll need better equipment to generate a 50 Hz signal.
• Verb
• to be a sign of (something)
1. Robins signal the arrival of spring.
2. The election results surely signal the start/beginning of a new era.
3. He signaled [=showed, communicated] his irritation by sighing and rolling his eyes dramatically.
4. Redness, swelling, and painful itching signal [=indicate] an infection.
5. A lock on the suitcase might signal that there's something of value inside.
• to make a sound or motion that tells someone something
1. Did he signal before he made the left turn?
2. They signaled at me to come over to their table.
3. We signaled for help.
4. He signaled us that it was time to begin the meeting.
5. The umpire signaled a strike.
• very important or great
1. Is he worthy of such a signal honor?
2. The bill's passage was a signal [=notable] victory for environmentalists.