semaphore
nounUK /ˈsɛməfɔː/
US /ˈsɛməfɔːr/
A semaphore is a way of sending messages using flags or lights that you move in different positions.
The sailors used semaphore to signal to the other ship.
RELATED WORDS
OTHER MEANINGS
2. A system of signaling using two flags held in different positions to represent letters.
The scouts learned semaphore to send messages across the field.
3. A railway signal consisting of a post with a movable arm.
The train slowed down when the semaphore turned red.
4. A visual signaling device using lights, such as on ships or towers.
The lighthouse used a semaphore to warn ships of the rocks.