signal

American  

[sig-nl] / ˈsɪg nl /

noun

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.

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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)

signaled, signaling, signalled, signalling

1. to make a token or indication to.

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

verb (used without object)

signaled, signaling, signalled, signalling

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

3. 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

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adjective

1. distinguished or conspicuous

2. used to give or act as a signal

verb

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

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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Other Word Forms

• presignal noun
• resignal verb
• signaler noun
• signaller noun
• unsignaled adjective
• unsignalled adjective

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”; sign, -al ², -al ¹

Example Sentences

By applying this effect to sequences of light pulses, including single photons, the researchers created a system where signals can effectively reconstruct themselves over time as they travel through optical fiber.

From Science Daily

“The labor market has been sending an unusual set of mixed signals,” John Williams, president of the New York Fed, said in a speech earlier this week.

From MarketWatch

Treasury yields were little changed as ambiguous signals from the White House about the path forward in the Middle East keep traders in a holding pattern.

From The Wall Street Journal

This year, the unusually warm weather in March, plant abundance and a healthy amount of prey were early signals to rattlesnakes to begin their activity.

From Los Angeles Times

Stocks rallied on the news Iran’s president signaled the country could be ready to end the war, though neither side has seemingly come to an agreement on terms.

From Barron's

Related Words

• alarm
• beacon
• cue
• gesture
• indicator
• sign