ntpdate is a deprecated computer program used to quickly synchronize and set computers' date and time by querying a Network Time Protocol (NTP) server. It is available for a wide variety of unix-like operating systems.
The accuracy and reliability of ntpdate entirely depends on the accuracy and network link stability of the first server it connects with. As this inaccuracy can lead to a multitude of problems, the maintainers have decided to deprecate it in favor of only using the ntpd (network time protocol daemon) or a sntp (simple network time protocol) query.
^Harlan Stenn (2012-09-02). "NTP.Org — Deprecating ntpdate". Retrieved 2012-10-30. The combination of ntpd and sntp now implements the functions of ntpdate. As soon as a few remaining issues with sntp are resolved the ntpdate program will be retired.