telegraphic signal vs signal

telegraphic signal and signal both are nouns.

Word	Noun	Adjective	Verb	Adverb
telegraphic signal	Yes	No	No	No
signal	Yes	Yes	Yes	No

As nouns, signal is a hypernym of telegraphic signal; that is, signal is a word with a broader meaning than telegraphic signal:

Other hypernyms of telegraphic signal include sign, signaling, signalling.

telegraphic signal (noun)	signal (noun)
a signal transmitted by telegraphy	any nonverbal action or gesture that encodes a message
	any incitement to action
	an electric quantity (voltage or current or field strength) whose modulation represents coded information about the source from which it comes

telegraphic signal (adjective)	signal (adjective)
	notably out of the ordinary

telegraphic signal (verb)	signal (verb)
	communicate silently and non-verbally by signals or signs
	be a signal for or a symptom of