In the vidui, we list our sins alphabetically, and for the samech, the word in my machzor is "sararnu" -- this is translated as "we have turned away."
After the list there is a paragraph which further discusses a consequence of (what I assumed was) all of our sins collectively, and this begins with "sarnu" -- also translated as "we have turned away."
Are the two terms simply different spellings of the same thing (and in that case, why are there two spellings) or do they refer to different types of sins, or attitudes about sin, or something else?
Textually, sar (in malachim 1, 20:43, 21:4 and 5) seems to mean "upset" while sarar (many uses) seems to be related to sor (as in ben sorer) which means to turn or stop (cf Yirmiyah 6:28, סָרֵי סוֹרְרִים , extremely perverse).
The other example of a doubled letter form I can think of quickly is mar and marar but both seem, textually, to refer to bitterness or sharpness and sadness.