semaphore

n. a system for sending messages using two flags or mechanical arms held in different positions to represent letters.

n. a visual signalling apparatus or system, typically involving two flags or mechanical arms, where specific positions correspond to alphabetic or numeric codes.

“The sailor used semaphore to send a message to the other ship across the water.”

“Before the advent of radio, naval vessels relied heavily on flag semaphore to communicate tactical instructions across short distances during daylight hours.”

n. a variable or piece of code that controls access to shared data so that only one process uses it at a time.

n. a synchronization mechanism, often a variable or abstract data type, used to control access to a common resource by multiple processes in a concurrent system.

“The developer added a semaphore to prevent two parts of the app from changing the same file at once.”

“The operating system utilizes a binary semaphore to ensure mutual exclusion, preventing race conditions when multiple threads attempt to write to the shared buffer simultaneously.”

Technical

v. to send a message using your arms or body movements instead of speaking.

v. to communicate information through visual gestures or signals, often used figuratively to describe exaggerated nonverbal communication.

“From across the crowded room, she semaphored her boredom by checking her watch repeatedly.”

“He stood on the balcony, frantically semaphoring his distress to the rescue team gathered in the valley below.”

Literary