sync2, synchalsosyncsomething ↔ up [intransitive and transitive]
to arrange for two or more things to happen at exactly the same time, or to happen at the same time or in the same way as something else [= synchronize]:
The hardest part was syncing the music to the video.
Wait for the computer to synch up with your command.
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.