A highly prominent disease.

Symptoms include unintentional (but repeated) misspellings of varying words in AIM conversations.

If you unintentionally misspell at least one word in every AIM chat, you suffer from Setoism.
Guy 1: So I was over at the moveis
Guy 1: *movies

Guy 2: Whoops, you've got Setoism.
by OmegaWeltall120 June 5, 2005
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