The word 'sync' is a modern, informal truncation of 'synchronize', which entered English in the 17th century from the Latin 'synchronus', itself derived from Greek 'súnkhronos'. The Greek source is a compound of 'sún-' meaning 'together, with' and 'khrónos' meaning 'time', literally translating to 'at the same time'. The 20th-century clipping 'sync' emerged from technical jargon, particularly in film and computing, where efficiency favored brevity. This evolution from a learned, multi-syllabic term to a concise, everyday verb perfectly illustrates language adapting to the pace of modern technology and communication.

The word is a clipped form of the longer word "synchronize" or "synchronization". It is not productively composed of smaller, independent morphemes in its current, shortened form.