1620s, "to occur at the same time," from Greek synkhronizein "be of the same time," from synkhronos "happening at the same time" (see synchronous). The transitive sense of "make synchronous" is first recorded 1806. Of timepieces by 1879. Related: Synchronized; synchronizing. Synchronized swimming is recorded from 1950.
<a href="https://www.etymonline.com/word/synchronization">Etymology of synchronization by etymonline</a>
Harper, D. (n.d.). Etymology of synchronization. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/synchronization