שֵׂטִים (also written סֵטִים) occurs in Tehillim 101:3 and Hoshea 5:2 and translates to something like "deeds/people that veer." Rashi on the verse from Hoshea connects this word to the root also found in the more common word סוטה sotah:
סטים - לשון כי תשטה אשתו (במדבר ה') לסור מן הדרך דישטולמנ"ט בלע"ז
Setim - This language is used in the verse "When his wife goes astray (tisteh)" (Bamidbar 5:12), meaning "to veer from the path". In La'az this word is distoulment.
In both occurences the word has a negative connotation (and semantically is similar to the word חטאים in the sense of "missing the mark") so it would make sense if this is why it is obfuscated in some books.
Incidentally, I think Google Translate gives "rebel" as a translation of שֵׂט because the verse from Hoshea is translated in the King James Bible with the word "revolters."
See also: Strong's Concordance H7846