semaphore

Noun

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

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.