A period of time, usually a week, that is used when "taking a break" from ones relationship in order to hook up with some other partner. Used in conjunction with a semi-truth or lie about why said break is needed, the safety week adds a period of time to the "initial break" to serve the purpose of appearing like the break was actually needed, and not thought up for the pleasure of "cheating".
How are you and Sarah doing?

-Ok, i wanna hook up with my friend over summer vacation so I'm gonna tell Sarah I need a break and then get with that other chick.

Won't it seem suspicious that you want to get back with Sarah RIGHT after you get back from vacation? You should use a safety week or two.
by Bumble-Puppy June 22, 2011
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