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a. An indicator, such as a gesture or colored light, that serves as a means of communication. See Synonyms at gesture.
b. A message communicated by such means.
2. Something that incites action: The peace treaty was the signal for celebration.
3. Biology A physical entity, such as a chemical or an electromagnetic wave, that activates a cell receptor and elicits a specific response.
a. Electronics An impulse or fluctuating quantity, as of electrical voltage or light intensity, whose variations represent coded information.
b. Computers A sequence of digital values whose variations represent coded information.
5. The sound, image, or message transmitted or received by means of telecommunications.
Notably out of the ordinary: a signal feat; a signal event.
v. sig·naled, sig·nal·ing, sig·nals or sig·nalled or sig·nal·ling
1. To make a signal to: I signaled the driver to proceed.
2. To relate or make known by signals: They have signaled their willingness to negotiate.
3. To cause an effect in (a cell) by the activation of a receptor, as by a neurotransmitter or hormone.
To make a signal or signals.

[Middle English, from Old French, from Medieval Latin signāle, from neuter of Late Latin signālis, of a sign, from Latin signum, sign; see sign.]

sig′nal·er, sig′nal·ler n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.signaling - any nonverbal action or gesture that encodes a messagesignaling - any nonverbal action or gesture that encodes a message; "signals from the boat suddenly stopped"
communication - something that is communicated by or to or between people or groups
recording - a signal that encodes something (e.g., picture or sound) that has been recorded
phone number, telephone number, number - the number is used in calling a particular telephone; "he has an unlisted number"
starting signal, start - a signal to begin (as in a race); "the starting signal was a green light"; "the runners awaited the start"
storm signal - a signal announcing the approach of a storm (particularly a storm of marked violence)
beam, radio beam - a signal transmitted along a narrow path; guides airplane pilots in darkness or bad weather
ticktack - system of signalling by hand signs used by bookmakers at racetracks
time signal - a signal (especially electronic or by radio) indicating the precisely correct time
dog-ear - a corner of a page turned down to mark your place
animal communication - communication between animals (of the same species)
alarum, warning signal, alarm, alert - an automatic signal (usually a sound) warning of danger
distress call, distress signal - an internationally recognized signal sent out by a ship or plane indicating that help is needed
all clear - a signal (usually a siren) that danger is over
bugle call - a signal broadcast by the sound of a bugle
curfew - a signal (usually a bell) announcing the start of curfew restrictions
retreat - (military) a signal to begin a withdrawal from a dangerous position
drumbeat - (military) the beating of a drum as a signal for lowering the flag at sundown
radiotelegraphic signal, telegraphic signal - a signal transmitted by telegraphy
whistle, whistling - the act of signalling (e.g., summoning) by whistling or blowing a whistle; "the whistle signalled the end of the game"
high sign - a silent signal of warning or recognition; "she started to speak but he gave her the high sign"
symbol - an arbitrary sign (written or printed) that has acquired a conventional significance
visual signal - a signal that involves visual communication
indicator - a signal for attracting attention
electronic signal - a signal generated by electronic means
radio beacon - a characteristic signal emitted by a transmitter used for navigation
input, input signal - signal going into an electronic system
output signal, output - signal that comes out of an electronic system
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
For verification of the new algorithm, it was used to decode real signaling signals measured on a train.
The Signal portion of the course taught field telegraph, field telephones, field buzzer, wireless signaling, and visual signaling.
These partial proceedings of the Cell Signaling world meeting of January 2006 in Luxembourg is the first in a series of four volumes; other volumes cover stress signaling and transcriptional control, cell signaling in health and disease, and inflammatory signaling pathways and neuropathology.
To see how hedgehog and other signaling pathways might affect fat development, endocrinologist Jonathan Graff of the University of Texas Southwestern Medical Center in Dallas and his colleagues studied the effects of activating and blocking the hedgehog and other pathways.
Therefore, the evaluation of the apoptosis and/or fibrosis process could be an excellent way of predicting the development of cardiomyopathy induced by SHS, although the specificity of the related signaling pathways involved in the development of apoptosis and/or fibrosis needs to be identified.
VC2, which is mapped to TC6 for error signaling, has two of the seven time slots.
Upon execution of the final agreement, the principal goals of the research program will be to advance the functional understanding of an undisclosed UOM protein in neurodegenerative diseases by researching its signaling pathways.
* A 4-kb/s data link that can be used for maintenance information, protection switching, supervisory signaling, or practically any other purpose.