From WordNet (r) 2.0 (August 2003) [wn]:
signal
adj : notably out of the ordinary; "the year saw one signal
triumph for the Labour party"
n 1: any communication that encodes a message; "signals from the
boat suddenly stopped" [syn: signaling, sign]
2: any incitement to action; "he awaited the signal to start";
"the victory was a signal for wild celebration"
3: an electric quantity (voltage or current or field strength)
whose modulation represents coded information about the
source from which it comes
v 1: 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" [syn: sign, signalize, signalise]
2: 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" [syn: bespeak, betoken, indicate,
point]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Signal \Sig"nal\, v. t. [imp. & p. p. Signaled or Signalled;
p. pr. & vb. n. Signaling or Signalling.]
1. To communicate by signals; as, to signal orders.
[1913 Webster]
2. To notify by a signals; to make a signal or signals to;
as, to signal a fleet to anchor. --M. Arnold.
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From The Collaborative International Dictionary of English v.0.48 [gcide]:
Signal \Sig"nal\, n. [F., fr. LL. signale, fr. L. signum. See
Sign, n.]
1. 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.
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All obeyed
The wonted signal and superior voice
Of this great potentate. --Milton.
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2. A token; an indication; a foreshadowing; a sign; anything
taken as evidence of some process.
[1913 Webster +PJC]
The weary sun . . .
Gives signal of a goodly day to-morrow. --Shak.
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There was not the least signal of the calamity to be
seen. --De Foc.
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3. Hence: (Electronics) A measureable electrical quantity,
such as voltage or current, that conveys information by
varying in magnitude over time; as, the signals from the
strongest commercial radio stations can be received over
hundreds of miles.
[PJC] Signal to noise ratio
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Signal \Sig"nal\, a. [From signal, n.: cf. F. signal['e].]
1. Noticeable; distinguished from what is ordinary; eminent;
remarkable; memorable; as, a signal exploit; a signal
service; a signal act of benevolence.
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As signal now in low, dejected state
As erst in highest, behold him where he lies.
--Milton.
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2. Of or pertaining to signals, or the use of signals in
conveying information; as, a signal flag or officer.
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The signal service, a bureau of the government (in the
United States connected with the War Department) organized
to collect from the whole country simultaneous raports of
local meteorological conditions, upon comparison of which
at the central office, predictions concerning the weather
are telegraphed to various sections, where they are made
known by signals publicly displayed.
Signal station, the place where a signal is displayed;
specifically, an observation office of the signal service.
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Syn: Eminent; remarkable; memorable; extraordinary; notable;
conspicuous.
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From The Free On-line Dictionary of Computing (19 Sep 2003) [foldoc]:
SIGNAL
<language> A synchronous language by Le Guernic et al of
INRIA.
["SIGNAL - A Data Flow-Oriented Language for Signal
Processing," P. le Guernic, IEEE Trans Acoustics Speech &
Signal Proc, ASSP-34(2):362-1986-04-374].
(1996-12-10)
From The Free On-line Dictionary of Computing (19 Sep 2003) [foldoc]:
signal
<operating system> A predefined message sent between two
Unix processes or from the kernel to a process. Signals
communicate the occurrence of unexpected external events such
as the forced termination of a process by the user. Each
signal has a unique number associated with it and each process
has a signal handler set for each signal. Signals can be sent
using the kill system call.
(1996-12-10)