synchronous

Etymology

Borrowed from Late Latin synchronus, from Ancient Greek σύγχρονος (súnkhronos, “contemporaneous”), from σῠν- (sun-, “with, together”) + χρόνος (khrónos, “time”); surface analysis, syn- + chron- + -ous = synchrony + -ous; however, all related words (e.g., synchronic, synchrony, synchronicity, diachronous, diachronic, diachrony, diachronicity) were coined later, either as back-formations from, or otherwise by analogy with the surface analysis of, synchronous.

adj

1. At the same time, at the same frequency.
2. (computing, of communication) Single-threaded; blocking; occurring in the same thread as other computations, thereby preventing those computations from resuming until the communication is complete.
   Post is a “fire and forget” where the UI thread work is performed asynchronously; Send is synchronous in that the call blocks until the UI thread work has been performed. 2014, Richard Blewett, Andrew Clymer, Pro Asynchronous Programming with .NET, page 25