[MENTION=95211]mudlock[/MENTION], actually this is the citation in Wikipedia:
The word "drow" is from the Orcadian and Shetlandic dialects of Scots,[5] an alternative form of "trow" (both of which come from the Nordic dökkálfar),[6] which is a cognate for "troll". The Oxford English Dictionary gives no entry for "drow", but two of the citations under "trow" name it as an alternative form of the word. Trow/drow was used to refer to a wide variety of evil sprites. Except for the basic concept of "dark elves", everything else about the Dungeons & Dragon drow was invented by Gary Gygax
This is pretty much diferent than Dragonborn (born from a dragon), or Tiefling (related to the devil), or even Halfling (people with half normal size). If you take the previous words I mentioned, you have a descritive of the race in the word. I don't just look at the meaning of the word, I look at how it fits the D&D world. Warlock for example, originaly it meant pact-breaker, in modern times it became a male wizard, sometimes associated with the devil, my translation of Pact-maker makes more sense than the original pact-breaker meaning, even thought its the exact opposite. Or even the Cavalier, originally they were an specific small knight order with no connections to the church, how is that related with the D&D cavalier?
Etimology is not everything if it doesn't accuratelly describes what the word means. Now, if I follow your advice and use the etymology for Drow:
Drow is a corruption of Trow, which means "evil sprite". Sprites, pixies, fairies, goblins, elves are all related and almost synonyms. Now, Trow has a cognate in english, Troll, which originally is a type of evil fairy/sprite. I don't really see how using the word Troll (or its portuguese equivalent Trasgo that is horrible and practically unknown) is of any good, or even desirable, considering we do have monsters called Trolls.
Why translate Feywild and not Arkhosia for example? Because the first does describe something, the second is a proper name. Drow and Eladrin are the same thing. We might find some obscure reference to Eladrin refering to wood elves in LotR, but that doesn't mean that I would change the name.
EDIT: Here is the definition of Trow from Britannica, it has nothing at all to do with the D&D drow.
in early Scandinavian folklore, giant, monstrous being, sometimes possessing magic powers. Hostile to men, trolls lived in castles and haunted the surrounding districts after dark. If exposed to sunlight they burst or turned to stone. In later tales trolls often are man-sized or smaller beings similar to dwarfs and elves. They live in mountains, sometimes steal human maidens, and can transform themselves and prophesy. In the Shetland and Orkney islands, Celtic areas once settled by Scandinavians, trolls are called trows and appear as small malign creatures who dwell in mounds or near the sea. In the plays of the Norwegian dramatist Henrik Ibsen, especially Peer Gynt (1867) and The Master Builder (1892), trolls are used as symbols of destructive instincts. Trolls in modern tales for children often live under bridges, menacing travelers and exacting tasks or tolls.
Here is the reasons/filter I use on why translate some term:
1) Does it have a direct counterpart in the target language? Mage, Fighter, Knight, Thief, Cleric, so on...
2) Do the term is an obvious derivative or compound word in the source language? Range(r), Dragon-born, Half-ling, Tief-ling, War-priest, Fey-wild, Shadow-fell...
3) Do the source term is constructed but has problems in pronunciation when used in the target language? Warlock, Hexblade...
4) If it you reached here, the term is a proper name, with no direct counterpart and no big problems with pronunciation, therefore you can safely use the source word. Drow, Eladrin, Pixie, Vryloka, Berserker...
