Pronounced with excessive exaggeration of the second "a", as in example 1. Shaddap is used to tell somebody to shut up without
sounding overly serious. It can also be used
pre-emptively, as in example 2. The crowning usage of shaddap however is as an unexpected end to a phrase, particularly when used to imply that somebody had said
something extremely stupid.
1. "Shaddaaaaaaaaaaaap."
2. "I know what you're going to
say, and I'm telling you, shaddap."
3. "How much more does a hard
drive weigh when full?"
"
Oh it weighs about shaddaaaap."