[1] : The Collaborative International Dictionary of English v.0.48

signal \sig"nal\, v. t. imp.  p. p. signaled or signalled;
   p. pr.  vb. n. signaling or signalling.
   1. to communicate by signals; as, to signal orders.
      1913 webster

   2. to notify by a signals; to make a signal or signals to;
      as, to signal a fleet to anchor. --m. arnold.
      1913 webster
see also:
signaled or signalled signaling signalling 

[2] : WordNet (r) 2.0

signaling
     n : any communication that encodes a message; "signals from the
         boat suddenly stopped" syn: signal, sign
see also:
signal sign 

Signaling >> S Words
Signaling, definition of term: Signaling
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