semaphore UK /ˈsɛm.əˌfɔː/US /ˈsɛm.əˌfoɹ/noun 3verb 1forms 3 noun3 •Any equipment used for visual signalling by means of flags, lights, or mechanically moving arms, which are used to represent letters of the alphabet, or words.The arms of the semaphore at the settlement were, in fact, gesticulating with comical vehemence. — 1875 •A visual system for transmitting information using the above equipment; especially, by means of two flags held one in each hand, using an alphabetic and numeric code based on the position of the signaller's arms; flag semaphore.As always in Lisbon, my heart throbbed semaphores to call Tónio. — 2008 •A bit, token, fragment of code, or some other mechanism which is used to restrict access to a shared function or device to a single process at a time, or to synchronize and coordinate events in different processes.The thread increments the semaphore to prevent other threads from entering the critical section at the same time. verb1 •(figurative) To signal using, or as if using, a semaphore, with the implication that it is done nonverbally.These gunny-sack chaps are not animals or savages. Look, Henry! They are semaphoring! See that tree there, and that big one across the cañon. Watch the branches wave. — 1920 formssemaphored · semaphoring · semaphores
