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semaphore

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noun sem·a·phore \ˈse-mə-ˌfȯr\

Definition of semaphore

  1. 1 :  an apparatus for visual signaling (as by the position of one or more movable arms)

  2. 2 :  a system of visual signaling by two flags held one in each hand

Recent Examples of semaphore from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'semaphore'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Illustration of semaphore

Origin and Etymology of semaphore

Greek sēma sign, signal + International Scientific Vocabulary -phore


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semaphore

verb sem·a·phore

Definition of semaphore

semaphored

;

semaphoring

  1. transitive verb
  2. :  to convey (information) by or as if by semaphore

  3. intransitive verb
  4. :  to send signals by or as if by semaphore

First Known Use of semaphore

1838


SEMAPHORE Defined for English Language Learners

semaphore

play
noun

Definition of semaphore for English Language Learners

  • : a system used for sending signals by using two flags that are held in your hands


SEMAPHORE Defined for Kids

semaphore

play
noun sem·a·phore \ˈse-mə-ˌfȯr\

Definition of semaphore for Students

  1. 1 :  a device for sending signals that can be seen by the receiver

  2. 2 :  a system of sending signals with two flags held one in each hand



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