> > Germanic *sunno:n <*swun- ?
> And why not simply *s(h2)un-,
The underlying n-variant of the heteroclitic stem is visible in the
derivative *sunþra- < *s(h2)wn.-t(e)ro- 'southern' = 'located on the
sun-side'.
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Arnaud
If one starts with *s-m?- "sun"
as I have suggested,
with the unconditionned : m? > w/H2w/wH2
or assimilation m?-t > nt
then *sunthra is from s°m?-tro
and the nasal is not a suffix but part of the root.
I hadn't thought about this word southern
but it confirms my analysis that
a certain number of PIE *w are from *m?-.
Arnaud