Etymology of the Latin word synchronus
the Late Latin word synchronus
derived from the Greek word sunchronos, σύνχρονος
using the Greek prefix sun-, συν-
derived from the Greek word sun, σύν (together; with or together ; by association, companionship, process, resemblance, possession, instrumentality, addition, etc.)
derived from the Greek word chronos, χρόνος (a space of time or interval; by extension, an individual opportunity; by implication, delay)