Meaning

Any equipment used for visual signalling by means of flags, lights, or mechanically moving arms, which are used to represent letters of the alphabet, or words..

Definitions by Sense

1. Any equipment used for visual signalling by means of flags, lights, or mechanically moving arms, which are used to represent letters of the alphabet, or words.
2. A visual system for transmitting information using the above equipment; especially, by means of two flags held one in each hand, using an alphabetic and numeric code based on the position of the signaller's arms; flag semaphore.
3. (programming) A bit, token, fragment of code, or some other mechanism which is used to restrict access to a shared function or device to a single process at a time, or to synchronize and coordinate events in different processes.
4. (ambitransitive, figurative) To signal using, or as if using, a semaphore, with the implication that it is done nonverbally.

Example Sentences

We must here take the liberty of expostulating with Sir Home [Riggs] Popham and the first Lord of the Admiralty, for having given to the telegraphic machine, invented by that gallant officer, the barbarous name of Semaphore, instead of Sematophore or Semophore—either of them ugly enough.

The large Silver Medal of the Society was this Session voted to Nic[h]olas Harris Nicolas, Esq. of the Inner Temple, for an Improvement on the Vertical Semaphore, and for his method of adapting a shifting Key to Telegraphic Communications, for the purpose of insuring their Secrecy. A Model of Mr. N's Semaphore has been placed in the Repository of the Society.

That the systems of telegraph and semaphore now in use are in a great measure use-less by night, and totally so in a fog, cannot be doubted; and that a mode, both rapid and secret, would could be put into practice at small expense, in fact little more than the first cost, would be of essential utility to the Government of the country adopting it, is equally true.

The arms of the semaphore at the settlement were, in fact, gesticulating with comical vehemence.

When, on long lines of stations, towers or other structures are used, it may be necessary, for greater speed, to sometimes employ semaphores for aerial telegraphy. [...] Semaphores consist of a post with arms. The arms starting with about three feet in length, to be increased one foot for every mile. These arms are made movable by ropes passing over wheels or pulleys, and moved by a crank below.

And so they went down, Jim steering by his father, turn for turn, over the Mayapur Bar, with the semaphores on each bank duly signalling the depth of water, [...]

Word Forms

• semaphores
• semaphoring
• semaphored

Related Words

When Should You Use Semaphore?

Use semaphore when its meaning, tone and grammar fit the full sentence. A synonym is not always a direct replacement.

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