Pronunciation: (sing'kru-nus),[key] —adj. 1. occurring at the same time; coinciding in time; contemporaneous; simultaneous.
2. going on at the same rate and exactly together; recurring together.
3. Physics,Elect.having the same frequency and zero phase difference.
4. Computers,Telecommunications.of, pertaining to, or operating using fixed-time intervals controlled by a clock (opposed to asynchronous).