semaphore
Flags convey messages
Semaphore is a system of visual signaling using flags, lights, or mechanical arms in fixed positions.
Each position represents a letter or message.
Railroad semaphores once controlled train traffic with movable arms.
In computing, a semaphore is a variable that coordinates access to shared resources, preventing conflicts when multiple processes run simultaneously.
The word extends to any system of coded signals: His raised eyebrow was a semaphore to change the subject.
Cloth symbol or signal
- pennantTapering nautical flag
- buntingFestive decorative fabric
- hoistRaise with tackle
- signallerOne who transmits signals
alphabet · visual · waving · movement · position · indicator · direction · manual
Message-conveying cue
clear · caution · mechanical · block · track · junction · distant · home
Mechanism requiring a key
- threadFiber for stitching
- synchronizationAligning timing across systems
- concurrencyOverlapping execution of tasks
- processSteps toward a result
resource · blocking · wait · signal · binary · counting · deadlock · acquire
Of the sea
- sailingWind-propelled water travel
- navalOf maritime warfare
- fleetVehicles under unified command
- regattaOrganized boat racing event
yachting · starboard · portside · bow · stern · mariner · seafaring · deckhand
Electrical message system
- transmissionSending of information
- cableHeavy-duty woven line
- radiotelegraphyCoded transmission via radio waves
- telexWired text transmission system
teleprinter · cablegram · relay · line · operator · key · sounder · wire
flag
Cloth symbol or signal
signaller · alphabet · visual · waving · movement · position · indicator · direction · manual · tower
signal
Message-conveying cue
stop · clear · caution · mechanical · block · track · junction · distant · home · quadrant
lock
Mechanism requiring a key
- threadFiber for stitching
- synchronizationAligning timing across systems
- concurrencyOverlapping execution of tasks
process · resource · blocking · wait · signal · binary · counting · deadlock · acquire · release
maritime
Of the sea
regatta · yachting · starboard · portside · bow · stern · mariner · seafaring · deckhand · captain
telegraph
Electrical message system
- transmissionSending of information
- cableHeavy-duty woven line
- radiotelegraphyCoded transmission via radio waves
telex · teleprinter · cablegram · relay · line · operator · key · sounder · wire · electrical
- communicationtelephone, conversation, inform, hand signal, messages
- trainstrains, train, locomotive, locomotives, steam locomotive
- communication methodsphone line, radio, telephone, television, text
- ways to communicatechat, announcement, gossip, broadcast, small talk
- codespassword, binary, DNA, RNA, QR code
- codes and cipherscipher, code, decode, decrypt, encrypt
semaphoretelepathy
Direct mental communication
spoken word · radio transmission · telephone · whisper · auditory signal
semaphoresecret code
Encrypted communication system
hidden message · steganography · cipher · dead drop · invisible ink
semaphoredigital communication
Information exchange via technology
satellite link · fiber optic · wireless signal · internet · email