semaphore

From Wiktionary

Noun[change]

Singular
semaphore

Plural
semaphores

The letter "F" as shown by semaphore flags
  1. Semaphore is a system of sending messages using lights, mechanical signals or flags.
    Railways use semaphore to send messages to trains.
  2. Semaphore is a system of sending messages using two flags to show each alphabet letter.
    Sailors use semaphore flags to send messages between ships.

Verb[change]

Plain form
semaphore

Third-person singular
semaphores

Past tense
semaphored

Past participle
semaphored

Present participle
semaphoring

  1. To semaphore is to send a message using a semaphore system.
    The sailor semaphored the nearby ship.