A nap taken when one is too lazy or tired to set an alarm and instead just hopes one will wake up in time for one's next engagement.

Often a bad idea and commonly results in the phrase "it seemed like a good idea at the time."
Shit, I'm four hours late for work! Why the hell did I take a sleep of faith? Ugh...it seemed like a good idea at the time...
by ProudGinger August 17, 2010
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