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Synonyms

signal

American  
[sig-nl] / ˈsɪg nl /

noun

  • signals
    plural
  1. anything that serves to indicate, warn, direct, command, or the like, such as a light, a gesture, an act, etc.: a signal to leave.

    a traffic signal;

    a signal to leave.

    Synonyms:
    sign
  2. anything agreed upon or understood as the occasion for concerted action.

  3. an act, event, or the like that causes or incites some action.

    The unjust execution was the signal for revolt.

  4. a token; indication.

    Synonyms:
    sign
  5. Electronics. an electrical quantity or effect, as current, voltage, or electromagnetic waves, that can be varied in such a way as to convey information.

  6. Cards. a play that reveals to one's partner a wish that they continue or discontinue the suit led.


adjective

  1. serving as a token or indication; used in communiating an intention, warning, or command.

    a signal flag.

  2. unusual; notable; outstanding.

    a signal exploit.

    Synonyms:
    striking, remarkable, exceptional, unique

verb (used with object)

  • signals,
    present (3rd person singular)
  • signaled,
    past participle,  past
  • signalled,
    past participle,  past (especially British)
  • signaling,
    present participle
  • signalling
    present participle (especially British)
  1. to make a token or indication to.

  2. to communicate or make known by a token or indication.

verb (used without object)

  • signals,
    present (3rd person singular)
  • signaled,
    past participle,  past
  • signalled,
    past participle,  past (especially British)
  • signaling,
    present participle
  • signalling
    present participle (especially British)
  1. to make communication by something that serves to indicate, warn, direct, command, or the like.

signal British  
/ ˈsɪɡnəl /

noun

  1. any sign, gesture, token, etc, that serves to communicate information

  2. anything that acts as an incitement to action

    the rise in prices was a signal for rebellion

    1. a variable parameter, such as a current or electromagnetic wave, by which information is conveyed through an electronic circuit, communications system, etc

    2. the information so conveyed

    3. ( as modifier )

      signal strength

      a signal generator

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. distinguished or conspicuous

  2. used to give or act as a signal

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to communicate (a message, etc) to (a person)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
signal Scientific  
/ sĭg′nəl /
  1. A fluctuating quantity or impulse whose variations represent information. The amplitude or frequency of voltage, current, electric field strength, light, and sound can be varied as signals representing information.


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Derived Forms

Inflected Forms

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Participles

Conjugated Forms

Present

Past

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Etymology

Origin of signal

First recorded in 1350–1400; Middle English noun from Old French seignal, signal, from Medieval Latin signāle, Late Latin, noun use of neuter of signālis “of a sign”; see sign, -al 2, -al 1


Explanation

A signal is a gesture or message that people use to communicate with each other. The wave you give a good friend to call her over from across the room and the impulse that transmits your voice through the telephone to your mother are both signals. In the course of a single day, you probably send and receive thousands of different signals. When you want to cross the street, you wait for the green light — a signal that it's safe to cross. If you're in a relationship and you're not sure whether you like the person you're dating, you could be sending mixed signals — first acting like you're interested, and then acting uninterested. If your date finally gets tired of your mixed signals while you're at a restaurant, you'll need to signal to your server that it's time for the check.

Keep Reading on Vocabulary.com

Vocabulary lists containing signal

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Christine Idzelis covered the reasons behind such a sharp tumble for the CoreWeave bonds and what they signal for bond and stock investors in other tech companies.

From MarketWatch ● Oct. 16, 2026

Its genetic instructions included a secretion signal that directs the enzyme outside the cell, along with a lipid anchor that holds it firmly to the cell membrane.

From Science Daily ● Oct. 16, 2026

Now retired, Paulsen publishes a Substack newsletter in which he revived an early warning indicator he’s used successfully as an economic signal in the past: the Walmart Recession Signal.

From The Wall Street Journal ● Oct. 15, 2026

Dr Kurr, from Bangor University, said that scientists were just starting to realise that "these wonderful animals can smell changes in water that signal a marine invasion which otherwise might have gone unnoticed".

From BBC ● Oct. 14, 2026

At Alexander’s signal, they started tracking, moving in zigzags and ever-widening circles with their noses first to the ground, and then lifted high in the air.

From "The Unseen Guest" by Maryrose Wood

There are also longer term signals for increased rainfall and storminess later in autumn and early winter in the UK.

From BBC ● Oct. 17, 2026

“Following upside data surprises this week, market participants will closely watch” his fireside chat for any signals regarding the Fed’s October meeting, CBA’s Carol Kong says in a research report.

From The Wall Street Journal ● Oct. 16, 2026

Use of the market path accomplishes at least two things that are important to Warsh: It preserves market signals and it gets the Fed out of forward interest-rate guidance.

From MarketWatch ● Oct. 16, 2026

They also help coordinate immune responses by sending signals that influence the behavior of other immune cells.

From Science Daily ● Oct. 16, 2026

He knew the signs and signals of moving rock.

From "Mountain of Fire" by Rebecca E. F. Barone

In a recent interview with The Times, Bass signaled her frustration with the slow pace of change within the LAPD.

From Los Angeles Times ● Oct. 16, 2026

The chip maker quietly signaled a new way of thinking about the competing demands of capital returns and building its AI ecosystem.

From The Wall Street Journal ● Oct. 13, 2026

China's economic planning body said in April the deal must be unwound, a move analysts said signaled the country's desire for greater control over homegrown tech.

From Barron's ● Oct. 8, 2026

The statement from the U.A.E.’s attorney general, Hamad Saif Al Shamsi, signaled that the co-pilot likely didn’t need to smuggle a weapon on board Wednesday’s Flight FZ1073 from Dubai to Tel Aviv.

From The Wall Street Journal ● Oct. 3, 2026

He slid off the wagon with that same fluid grace and signaled the still-spooked knuckleskull to fall back.

From "Dactyl Hill Squad" by Daniel José Older

Their report also signalled the presence of South American military contractors but could not identify who employed them.

From Barron's ● Oct. 16, 2026

The mother of murderer Vickrum Digwa could be in line for deportation from the UK, the Home Office has signalled.

From BBC ● Oct. 15, 2026

Around 20 minutes after these codes were signalled, the plane looped back into Saudi Arabia, where it later started its manual descent for landing.

From BBC ● Oct. 1, 2026

The paper says investors have signalled that the gilt market "would not be spooked" by a more modest target, adding that the Treasury and Number 10 are "actively debating" the possibility.

From BBC ● Sep. 24, 2026

He smiled and, one hand hold­ing onto the railing, the other waving, signalled me to come over.

From "Life of Pi" by Yann Martel

Apple customers who preorder the new iPhone Duo now will not receive the device until the end of January, signaling strong demand.

From Barron's ● Oct. 16, 2026

It would retire the dot plot and get the Fed out of signaling its next few moves, while also giving policymakers a common baseline to comment on.

From MarketWatch ● Oct. 16, 2026

The pathological neurovascular environment describes the abnormal interactions between those vessels and pain signaling nerves in the affected tissue.

From Science Daily ● Oct. 14, 2026

Inflammation within the joint, changes in surrounding tissues, and increased sensitivity of pain signaling nerves can all contribute to persistent discomfort.

From Science Daily ● Oct. 14, 2026

One boy pointed at us and started our way, signaling to the others to follow.

From "It All Comes Down to This" by Karen English

In 1969, moments before the historic Apollo 11 Moon landing, an onboard computer raised an alarm, signalling an error was occurring.

From BBC ● Oct. 8, 2026

The China Securities Regulatory Commission recently held informal talks with some investment banks and institutional investors, signalling a higher bar for humanoid-robotics companies seeking to go public, according to people familiar with the matter.

From The Wall Street Journal ● Sep. 9, 2026

Munira Mustaffa, a Malaysia-based counterterrorism and extremism expert, said they were "frustrated signalling" by insurgents intended to "get the government to return to the table".

From Barron's ● Aug. 26, 2026

"As Bessent himself confirmed, the move is mainly a signalling mechanism, with the Treasury showing it is prepared to step in with yields near current levels," said economists at Capital Economics.

From BBC ● Aug. 21, 2026

"Hello, there," I began, and when he turned toward the crowd and whistled I didn't know whether he was telling me to do the same or signalling to someone else.

From "Invisible Man" by Ralph Ellison

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