An expression meaning that one has been surprised by what has just occured. It is similar to saying "wow" or "holy crap" but implies a more laid back manner.
"So did you see the new... OH SNAP! A guy just ran buy with a katana!"
Used in taunting your manager when you make comments on his wife leaving him due to infidelity.
Me: "Hey scott I did your wife last night, not that it matters because she left your sorry ass anyway when she caught you screwing 18 year olds"
Derek: "OH SNAP!"
(exclamatory phrase) a playful indication of surprise, misfortune, or insult
popularized by Tracy Morgan of Saturday Night Live, OH SNAP is seemingly derivative of oh no you didn't where an insulted person, for example a guest of Jerry Springer or often a spunky African American woman contends the insult being made against him/her. While derivative of "oh no you di-int," OH SNAP has more of an emphasis on playfulness and can be said by people other than those being insulted.
see also: OH ZIP
Ted: Man, where you been all afternoon?
Darrin: I had to stop off at your mom's place for a nooner that last a bit longer than expected.
Sister: This meeting was to discuss the rough draft of my essay, where we discussed the subsidiary questions I added in my rough draft. We also discussed the relationship between my main title and the real-life situations I chose to use in my essay. We discussed the structure of my essay as well, specifically the Math AOK section and how it relates to the contradiction of the title. This second meeting was particularly helpful in discussing the implications of my essay claims and how to apply the title across various areas of knowledge. There were many sections of the essay that could have been cut down in wordiness and the ways of knowing required further and more in-depth analysis.