A Sindarin name for Ossë, a combination of gaer “dreadful” and a reduction of his ancient Sindarin name †Yssi (WJ/400). Tolkien stated that this name “was more often used by the inland Teleri”, who viewed this Maia with more awe and fear. Otherwise he was known as Yssion.
Conceptual Development: In the Gnomish Lexicon from the 1910s, the Gnomish name of Ossë is G. Oth(a) (GL/18), perhaps derived from G. ô “sea” (GL/61). In The Etymologies from the 1930s, his Noldorin name is N. Aeros >> Oeros (Ety/GOS, EtyAC/GOS), perhaps a combination of N. oer “sea” and the root ᴹ√GOS “dread”.