(n.)A deviation from normal English coined by Seth, normally used when one is instant messaging friends, that is distinguished by the prefix "o.o" (or, less commonly, "o_o" or "-_-", depending on the context) and followed immediately by a phrase or sentence in which there are no spaces between the words. It's most commonly used to express surprise, curiosity, frustration, or annoyance, but shouldn't be used repeatedly due to possible annoyance of the recipient. Sethspeak is ordinarily only used for short phrases, since the meaning can become distorted (or lost altogether) more easily as more words are added. In addition, there is very little punctuation in sethspeak, since it breaks up the flow of the sethspeak phrase (thereby defeating the purpose). An exception is the use of question marks or exclamation points at the very end of the phrase, and apostrophes at the speaker's discretion in contractions. Also, when the phrase begins with the letter "o" and the prefix "o.o" is used, the phrase's "o" is omitted so as to prevent redundancy, e.g. "o.omg" instead of "o.oomg".

Note that the prefix "o.o" or a variation MUST be included. If it isn't, the phrase no longer qualifies as sethspeak. Some leet (or 1337) may be used in the phrase, but an entirely leet sethspeak phrase is usually extremely difficult to read and therefore rarely seen.
Person 1: o.omgyou'llneverguesswhathappenedtoday
Person 2: 0.0heaskedyouout!!
Person 1: -_-no

Person 3: o.oeliiknowyou
Person 4: o.oreally?
Person 3: o.oyes
Person 4: o.oyou'rean00b
Person 3: o.onoyouare
Person 4: OK, enough with the sethspeak -_-
by Frau Sabre May 15, 2006
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