anything that serves to indicate, warn, direct, command, or the like, such as a light, a gesture, an act, etc.: a traffic signal;a signal to leave.
anything agreed upon or understood as the occasion for concerted action.
an act, event, or the like that causes or incites some action: The unjust execution was the signal for revolt.
a token; indication.
Electronics. an electrical quantity or effect, as current, voltage, or electromagnetic waves, that can be varied in such a way as to convey information.
Cards. a play that reveals to one's partner a wish that they continue or discontinue the suit led.
serving as a token or indication; used in communiating an intention, warning, or command: a signal flag.
unusual; notable; outstanding:a signal exploit.
to make a token or indication to.
to communicate or make known by a token or indication.
to make communication by something that serves to indicate, warn, direct, command, or the like.
- sig·nal·er; especially British sig·nal·ler, noun
- pre·sig·nal, noun, verb (used with object), pre·sig·naled, pre·sig·nal·ing or (especially British) pre·sig·nalled, pre·sig·nal·ing.
- re·sig·nal, verb re·sig·naled, re·sig·nal·ing or (especially British) re·sig·nalled, re·sig·nal·ling.
- un·sig·naled, adjective
- un·sig·nalled, adjective
- signal , single
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use signal in a sentence
The poll also signalled that Americans were comfortable with targeted military action again Iran in the worst-case scenario.
Stainless signalled higher BTUs coming out of the burners, bigger ovens, and so forth.
President Obama signalled his move to a middle strategy in his Tuesday meeting with Congressional leaders.
With his hat he signalled his brother to steer for the General Price, and on the two rams rushed, the Queen slightly ahead.The Courier of the Ozarks | Byron A. Dunn
In the evening hung about waiting for de Robeck who had signalled over to say he wanted to talk business.Gallipoli Diary, Volume I | Ian Hamilton
It was afterwards ascertained that a mistake had been made in reference to the vessel that had signalled.The Floating Light of the Goodwin Sands | R.M. Ballantyne
He signalled the porter, who opened one of the big glass doors and signified that the countess could depart.The Weight of the Crown | Fred M. White
He called to her, he rallied her; he signalled to Thyrsis to help him—to inspire her, to goad her to new endurance.Love's Pilgrimage | Upton Sinclair
British Dictionary definitions for signal
any sign, gesture, token, etc, that serves to communicate information
anything that acts as an incitement to action: the rise in prices was a signal for rebellion
a variable parameter, such as a current or electromagnetic wave, by which information is conveyed through an electronic circuit, communications system, etc
the information so conveyed
(as modifier): signal strength; a signal generator
distinguished or conspicuous
used to give or act as a signal
to communicate (a message, etc) to (a person)
- signaller or US signaler, noun
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
Scientific definitions for signal
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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.