I don't think these are exclusive to The Pit, but they appear here.
Doughtful: Intentional misspelling of the word "doubtful".
Ghey: Intentional misspelling of the word "gay". Often preceded by "teh" (see above). Misspelling almost always used, except when referring to
Sirgay: Refers to WIS member and frequent poster sergei91.
Definately: Possibly unintentional misspelling of the word "definitely". I have seen the mistake on other forums.