A fork of Rural Dictionary
When someone sets an alarm clock, but wakes up just before it actually goes off. Usually as a result of the brain anticipating that it will suddenly be awoken by a loud sound and therefore you awake without the need of the alarm.
"I don't know why I keep setting my alarm every morning, because I just end up waking up 10 minutes before it goes off". "That's an Anticipation Awakening my good friend".