As far as I know there was never a clear translation of the name of
_Thranduil_ (in fact none at all?), so I wonder what the actual
meaning might be. My only idea so far:
it could consist of _staran-_, which in Etym. leads to Ilkorin words
containing "stiff, hard", and possibly *_tujloo_ as analogical
agental form of *_tujlee_ (spring). There doesn't seem to be an
etymological problem (*Starán-tujloo > S *Sthran-tuilo > Thran-duil),
if the semantic border between the terms was always recognized, but
already this is not _that_ likely, and even worse "Hard Spring"
doesn't make much sense.
So maybe *_-loo_ is a variant of _-roo_, so just a mere agental
ending attatched to the unchanged stem, leading to an interpretation
of something like "Offspring of the Hard (Ones)"?
Neither one seems really likely to me (although I really believe it
may contain _staran-_), but I should like to hear your ideas.
Florian "Lothenon" Dombach