• Awaiting the signal to attack
    Awaiting the signal to attack
  • WordNet 3.6
    • adj signal notably out of the ordinary "the year saw one signal triumph for the Labour party"
    • v signal be a signal for or a symptom of "These symptoms indicate a serious illness","Her behavior points to a severe neurosis","The economic indicators signal that the euro is undervalued"
    • v signal communicate silently and non-verbally by signals or signs "He signed his disapproval with a dismissive hand gesture","The diner signaled the waiters to bring the menu"
    • n signal any nonverbal action or gesture that encodes a message "signals from the boat suddenly stopped"
    • n signal any incitement to action "he awaited the signal to start","the victory was a signal for wild celebration"
    • n signal an electric quantity (voltage or current or field strength) whose modulation represents coded information about the source from which it comes
    • ***

Additional illustrations & photos:

The Signal Corps The Signal Corps
Wig Wag Signalling Wig Wag Signalling
Signals that Guards our Coast Signals that Guards our Coast
The Signal of Distress that was Never Seen The Signal of Distress that was Never Seen

Webster's Revised Unabridged Dictionary
  • Interesting fact: Toronto was the first city in the world with a computerized traffic signal system
    • Signal A sign made for the purpose of giving notice to a person of some occurence, command, or danger; also, a sign, event, or watchword, which has been agreed upon as the occasion of concerted action. "All obeyed
      The wonted signal and superior voice
      Of this great potentate."
    • Signal A token; an indication; a foreshadowing; a sign. "The weary sun . . . Gives signal of a goodly day to-morrow.""There was not the least signal of the calamity to be seen."
    • Signal Noticeable; distinguished from what is ordinary; eminent; remarkable; memorable; as, a signal exploit; a signal service; a signal act of benevolence. "As signal now in low, dejected state
      As erst in highest, behold him where he lies."
    • Signal Of or pertaining to signals, or the use of signals in conveying information; as, a signal flag or officer.
    • Signal To communicate by signals; as, to signal orders.
    • Signal To notify by a signals; to make a signal or signals to; as, to signal a fleet to anchor.
    • ***
Century Dictionary and Cyclopedia
  • Interesting fact: The first British ship to use the SOS distress signal was the Titanic
    • signal Constituting, or serving as, a typical sign or index; especially conspicuous or noteworthy; strikingly uncommon: as, a signal example; a signal failure; signal prosperity.
    • signal Of high grade or quality; eminent; great; elevated: applied to persons and feelings.
    • signal Synonyms Conspicuous, extraordinary.
    • n signal Sign; token; indication.
    • n signal A conventional or intelligible sign designed for information or guidance; an object displayed, a motion made, a light shown, a sound given out, or the like, for direction to or communication with a person or persons (especially at a distance) apprised of or able to recognize its intended meaning: as, to hoist, sound, or make a signal; military and naval signals; a warning signal; a book of signals (see signal-book). Occasions for the use of formal signals abound particularly in military operations, navigation, railroading, and telegraphing (especially by means of semaphores); and the methods and devices employed are almost innumerable. See cut under semaphore.
    • n signal An inciting action or movement; an exciting cause; an initial impulse: as, this tyrannous act was the signal for insurrection.
    • signal To mark with a sign.
    • signal To communicate or make known by a signal or by signals: as, to signal orders; a vessel signals its arrival.
    • signal To make signals to: as, the vessel signaled the forts.
    • signal To he a sign or omen.
    • signal To give a signal or signals; make communication by signals.
    • n signal In whist, any method of showing that the player wants trumps led. See trumps signal.
    • ***
Chambers's Twentieth Century Dictionary
  • Interesting fact: David Sarnoff received the Titanic's distress signal and saved hundreds of passengers. He later became the head of the first radio network, the National Broadcasting Company (NBC).
    • n Signal sig′nal a sign for giving notice, generally at a distance: token: the notice given: any initial impulse
    • v.t., v.i Signal to make signals to: to convey by signals:—pr.p. sig′nalling; pa.t. and pa.p. sig′nalled
    • adj Signal having a sign: remarkable: notable: eminent
    • ***


  • Oliver Wendell Holmes
    “Stillness and steadiness of features are signal marks of good breeding. Vulgar persons can't sit still, or at least must always work their limbs and features.”
  • John Updike
    “For male and female alike, the bodies of the other sex are messages signaling what we must do -- they are glowing signifiers of our own necessities.”
  • A. H. K. Boyd
    A. H. K. Boyd
    “There are important cases in which the difference between half a heart and a whole heart makes just the difference between signal defeat and a splendid victory.”
  • Source Unknown
    Source Unknown
    “If a woman driver ahead of you signals a left turn, be careful, she may turn left.”
  • Napoleon Hill
    “When defeat comes, accept it as a signal that your plans are not sound, rebuild those plans, and set sail once more toward your coveted goal.”
  • Dorothy Sarnoff
    Dorothy Sarnoff
    “Never try to look into both eyes at the same time. Switch your gaze from one eye to the other. That signals warmth and sincerity.”


Webster's Revised Unabridged Dictionary
F., fr. LL. signale, fr. L. signum,. See Sign (n.)


In literature:

On hearing it, thus uttered as a signal of defiance, the eyes of the tigrero began to sparkle with an irresistible desire for the chase.
"The Tiger Hunter" by Mayne Reid
He glanced up fifteen yards away where Tough McCarty stood waiting the starting signal.
"The Varmint" by Owen Johnson
Odell, the Brigade Signalling Officer, who later on became a great friend.
"Q.6.a and Other places" by Francis Buckley
The three men exchanged glances, then, as at a signal, stepped forward and surrounded him.
"The Young Railroaders" by Francis Lovell Coombs
He gathered around him a retinue of young men who were ambitious to signalize themselves.
"An Historical Account of the Settlements of Scotch Highlanders in America" by J. P. MacLean
Finally, she must exact a signal revenge for the assassination of the Archduke.
"World's War Events, Vol. I" by Various
The whoops, signals and reports of the guns could not fail to tell the whole story, and to cause the Pawnees to converge toward the spot.
"Footprints in the Forest" by Edward Sylvester Ellis
Immediately Morgan noted the exact spot from which the firing came, so he could locate it in sending out his signal of warning.
"Air Service Boys Flying for Victory" by Charles Amory Beach
When they had gone about a mile all stopped at a signal from White Lightning.
"The Riflemen of the Ohio" by Joseph A. Altsheler
At the same instant, they saw the signal go to the mast-head of Zoutman's ship.
"Memoirs and Correspondence of Admiral Lord de Saumarez, Vol. I" by Sir John Ross

In poetry:

Went down to the yards
To see the signal lights come on;
Looked down the track
Where my lovin' babe done gone.
"Long Track Blues" by Sterling A Brown
All lore our Lady Venus bares,
Signalled it was or told
By the dear lips long given to theirs
And longer to the mould.
"Our Fathers Also" by Rudyard Kipling
Whose fleets have lit the caverns of the deep,
Whose wings have breasted all the winds that blow,
And flashed his signal from his airy keep
To worlds above, below.
"Ad Astra" by George Essex Evans
Dick left the line, and it never was known
Where he went; but often I think of that day,
And still by the bridge I can hear him say,
"We must signal to Bill as we journey down."
"Bill's Length" by Alexander Anderson
We passed where flag and flower
Signalled a jocund throng;
We said: "Go to, the hour
Is apt!"—and joined the song;
And, kindling, laughed at life and care,
Although we knew no laugh lay there.
"Middle-Age Enthusiasms" by Thomas Hardy
'Tis the twilight of Sabbath,--and sweet through the air,
Swells the blast of the bugle, that summons to prayer:
The signal is answered, and soon in the glen
Sits Colonel Dunbar in the midst of his men.
"Beechenbrook - VII" by Margaret Junkin Preston

In news:

More VC But Fewer Deals Signal That Investors Are Becoming Even More Risk Averse .
Ashton Kutcher's Twitter Victory Over CNN Signals the Dawn of a New Era of Awesomeness .
The Wine Country 2301 Redondo Ave Signal Hill 562-597-8303.
When will the blinking signal at Hwy 51 and Lebanon start working.
New coach signals new start for Bluejay women's program.
Signal Mountain High School football team stripped of 6 wins by TSSAA.
One ref signals a touchdown.
The other signals an interception.
Tom Hauck Lexington Catholic (Lexington, Ky.) junior signal-caller Kyle Bolin threw for 3,088 yards and 29 touchdowns this past fall to help lead his team to the state semifinals.
What's the best way to get A/V signals across a room.
Like the router in a computer network, the brain's version can be reconfigured to send signals to different locations.
WASHINGTON — One day CIA Director David Petraeus was sending out signals he'd like to stay on for President Barack Obama's second term.
Promax Electronica has unveiled a new test and measurement device designed for fix and mobile signal monitoring in DVB-T and DAB broadcast systems.
Similar Early Warning Signals of Change in Climate.
COLUMBIA—Missouri's white-tailed deer continue to be killed by a disease transmitted by midge flies, but the recent cold weather might be signaling an end to the outbreak.

In science:

We found that the probability that PM is higher than 0.001 is about 9% for the signal filtered with Ψ and less than 10−5 for the signal filtered with Φ.
On Optimal Detection of Point Sources in CMB Maps
The random MRFM signal which follows the regular signal shown in Fig. 3.
Regular and Random Magnetic Resonance Force Microscopy Signal with a Cantilever Oscillating Parallel to a Sample Surface
We present here two examples to illustrate the relevance of the proposed dictionaries to a typical problem of signal representation: the problem of achieving a sparse atomic decomposition approximating a given signal.
Cardinal B-spline dictionaries on a compact interval
As soon as the sources finish computing the data, they emit certain signal(s) triggering the computation of the corresponding data on the following modules and then wait for ack-signals from them.
EPspectra: A Formal Toolkit for Developing DSP Software Applications
Therefore, for a security analysis, we may suppose that a source emitting weak coherent state signals is actually emitting signals in the state ρµ .
Phase randomization improves the security of quantum key distribution