: : : :
: : : : If Sauron means "abominable" in Quenya, then it was given to him after his corruption by Melkor. What was his original name?

: : I think "Thu" was just a linguistically older version of Sauron/Gorthaur. 'th' is often converted to 's' (and vice-versa) when languages evolve, and it's easy to think of 'u' changing to the diphthong 'au'. In the Sindarin "Gorthaur", the "gor-" could be left off (it's adjectival, strengthening the meaning of "thaur"), leaving just "thaur", which is remarkably close to both "thu" and "sauron".

: : The names were probably given to the Ainur sometime after they came down to Arda, seeing as how the names are tightly meshed with their roles in Arda. Since Sauron revolted so early, perhaps he never had another name.

: A Boy Named Sue? No wonder Sauron was angry. Sorry, this topic is ripe for name jokes. I couldn't resist.

Hahahahaha!!!!!!