Pronunciation: (sem'u-fôr", -fōr"), [key]
—n., v., -phored, -phor•ing.
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.
to signal by semaphore or by some system of flags.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.