semaphore
semaphore Lexical Profile
semaphore Game Scores & Validity
• noun
A system of sending messages by holding the arms or two flags or poles in certain positions according to an alphabetic code, or a mechanical apparatus with movable arms used for visual signaling (especially on railways).
"Before modern radio communication, sailors often relied on flag semaphore to relay messages between ships at sea."
In computer science, a variable or abstract data type used to control access to a common resource by multiple processes or threads in a concurrent system.
"The programmer implemented a binary semaphore to prevent two threads from modifying the shared database simultaneously."
• verb
To send a message or signal by semaphore, or to gesture in a way that resembles visual signaling.
"The deckhand semaphored the harbor master to request permission to dock."
Word Origin & Etymology
Borrowed in the early 19th century from French sémaphore, which was coined from Ancient Greek sêma ('sign, signal') and phorós ('bearing, carrying').