I was surprised not to see any correction for Ambaroone in Ety:348,
in Vinyar Tengwar 45.
It always looked to me a as typo for Ambaroona. Hammond in
his "Artist and Illustrator", p. 197 cites "Ambaroona" (sic) as from
(N.B. In LOTR II Ambarona is a typo in some printings for Ambaroona.)
As for the meanings looks as to be :
1° uprising (esp. sunrise)
2° Orient ; Poét. the East of the World ; the Hills of Morning or
the Gates of Morn(nings).
For Fangorn that forest was in Orient as compared to Beleriand, and
[The reading _Ambaróne_ in the published _Etymologies_ s.v.
AM(2)- 'up' is unquestionably correct. If there had been any
doubt as to the identity of the final vowel, Carl and I would
have noted this in the A&C.
For the sake of clarity, I will repeat here what I said in an editorial
note to Ales Bican's message #565:
"For future reference, readers of the A&C can assume that
corrigenda presented using the formula "[for:] THIS [read:] THAT"
are certain. If there is any uncertainty about the correct reading,
this is _always_ indicated, most often by the formula
"[for:] THIS [perhaps read:] THAT"."
To which I will now add the corollary: Any form in the published
_Etymologies_ that is not mentioned in the A&C can be assumed
to be correct.