/sem"euh fawr', -fohr'/, n., v., semaphored, semaphoring.n.1. an apparatus for conveying information by means of visual signals, as a light whose position may be changed.2. any of various devices for signaling by changing the position of a light, flag, etc.3. a system of signaling, esp. a system by which a special flag is held in each hand and various positions of the arms indicate specific letters, numbers, etc.v.t., v.i.4. to signal by semaphore or by some system of flags.[1810-20; < Gk sêma sign + -PHORE]
* * *Method of visual signaling, usually with flags or lights.Before radio, a semaphore system was widely used to send messages between ships. A person would stand with arms extended, moving two flags to specific angles to indicate letters or numbers. Before the invention of the telegraph, semaphore signaling with lights on high towers was used to transmit messages between distant points; messages were read by telescope. Modern semaphores have included movable arms or rows of light simulating arms, displayed from towers and used to signal railroad trains.
* * *method of visual signaling, usually by means of flags or lights. Before the invention of the telegraph, semaphore signaling from high towers was used to transmit messages between distant points. One such system was developed by Claude Chappe (Chappe, Claude) in France in 1794, employing a set of arms that pivoted on a post; the arms were mounted on towers spaced 5 to 10 miles (8 to 16 km) apart. Messages were read by telescopic sightings. Modern semaphores included movable arms or rows of lights simulating arms, displayed from towers and used to signal railroad trains. Semaphore signaling between ships, now largely abandoned, was accomplished by persons who held a small flag in each hand and, with arms extended, moved them to different angles to indicate letters of the alphabet or numbers.
* * *