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1. Any nonverbal action or gesture that encodes a message
   "signals from the boat suddenly stopped";
   - signaling [N. Amer], sign, signalling [Brit, Cdn]
    
2. Any incitement to action
   "he awaited the signal to start"; "the victory was a signal for wild celebration"
    
3. An electric quantity (voltage, current or field strength) whose modulation represents coded information about the source from which it comes

1. Communicate silently and non-verbally by signals or signs
   - sign, signalize, signalise [Brit]
    
2. Be a signal for or a symptom of
   "The economic indicators signal that the euro is undervalued";
   - bespeak, betoken [archaic], indicate, point

1. Notably out of the ordinary
   "the year saw one signal triumph for the Labour party"

Derived forms: signalling, signalled, signals, signaled

See also: impressive

Type of: communicate, communication, electrical energy, electricity, incitation, incitement, intercommunicate, leccy [Brit, informal], power, provocation, tell

Encyclopedia: Signal, Ohio