A daybagger is a stock that rises at least as much per share in a single day as your original cost basis. At The Motley Fool, the verb form of this term is spiffy-pop.

For example, a stock rises from $98 to $100 per share, and you originally paid a cost-adjusted $1.50 for it. That $2 gain is greater than your cost basis -- and that, my friends, is a "daybagger." And it's a sweet thing.

In 2007, David Gardner asked the Rule Breakers community to help him invent a word to capture this phenomenon. At least five Fools came up with daybagger as the perfect noun. As David explained, it elegantly dovetails with our use of 'bagger' at Fool.com -- where we call, for instance, a stock that triples a 'three-bagger.'"

A mere two days after announcing the winning words, Rule Breakers experienced a first, as one of its recommended stocks spiffy-popped: Software maker aQuantive received a buyout offer from Microsoft and gained more than $38 that day. From its recommendation price of $25, that made aQuantive our first daybagger!

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