Main Entry: ¹sem·a·phore

Pronunciation: \ˈse-mə-ˌfȯr\

Function: noun

Etymology: Greek sēma sign, signal + International Scientific Vocabulary -phore

Date: 1816

1 : an apparatus for visual signaling (as by the position of one or more movable arms)
2 : a system of visual signaling by two flags held one in each hand

[semaphore illustration]