Other forms: signals, signalled, signalling
A signal is a sign sent on purpose, to reach somebody who is watching or listening for it. Two bars on your phone, a hand out of a car window, a green light at the far end of the platform.
The word covers the message and the thing carrying it at the same time: a radio signal, a weak signal in the hills, a signal that dies the moment the lift doors close. As a verb you signal a turn, and you can signal something without meaning to — a shrug at the wrong moment signals that you do not care. Governments and companies use it that way on purpose, sending a signal to the markets, giving a signal of intent, saying a thing without announcing it. There is an adjective signal too, meaning notable, as in a signal achievement; it is formal and old-fashioned and it will surprise people.
1nounsignalThe waves that carry a phone call, sound or pictures, and how strong they are.~64%
“There is no signal down in the valley.”
synonyms: reception
2noungestureA movement, light or sound sent on purpose to tell somebody something.~26%
“He gave the signal and everyone stood up.”
3verbknownTo make a sign to somebody, or to make something known without saying it outright.~8%
“She signalled left and pulled over.”
4nounrailThe light or arm beside a railway line that tells a driver to stop or go.~2%
“The train stood outside the station at a red signal.”
Shares are an estimate: a language model read 168 sentences found in the wild and placed 157 of them on a sense (11 were unclear) — a count of our sample, not a measurement of English.
Also accepted in games: reception
English took one Latin word twice over. Signum, a mark, came in early and plainly as sign; then Medieval Latin made signāle out of it, the thing that carries the mark, and that came in through Old French as signal. The difference has held ever since. A sign is simply there; a signal is aimed at somebody.
Proto-Indo-European
*sekʷ-
Latin
signālis
Medieval Latin
signāle
Old French
segnal
English, today
signal
From Old French segnal, seignal or Medieval Latin signāle; noun use of the neuter of Latin signālis, from Latin signum; verb use from 1805, as a shortened from signalize (1650s). a doublet of signum and sign.
Etymology from Wiktionary, CC BY-SA