Re:0-day exploit for Internet Explorer in the wild
by tlrobinson on Wednesday December 10, 2008 @05:35PM
(#393587)
"A zero-day (or zero-hour) attack or threat is a computer threat that tries to exploit unknown, undisclosed or patchfree computer application vulnerabilities."
"The term zero-day can also be used to describe warez-group releases of pirated software on or before the release of the software."
"The term zero-day can also be used to describe warez-group releases of pirated software on or before the release of the software."
http://en.wikipedia.org/wiki/Zero-Day_Attack
I think "zero-day attack/exploit" is basically a euphemism for "oh shit, didn't see that one coming"