Definitions
1.NounA guard dog.
2.NounAn individual or group that monitors the activities of another entity (such as an individual, corporation, non-profit group, or governmental organization) on behalf of the public to ensure that entity does not behave illegally or unethically.
3.NounEllipsis of watchdog timer.
4.VerbTo perform a function analogous to that of a watchdog; to guard and warn.
5.VerbTo be continuously reset by a watchdog timer.