1. The critical period of time on a night out, before which it is too early to drop, and after which it is too late to drop. It is largely dependant upon which DJs are playing when, and what time the club closes or the night ends.
"Dude, we better bosh a few now, the window of dropportunity is closing fast"
1. To confuse the identity of one person with another
"Woah, dude, totally misrecognised you there. Thought you were someone else"