druid

I think it was Piotr(?) who brought it up the Bartleby link awhile
back...

IE root "deru" / "dreu":
http://www.bartleby.com/61/roots/IE87.html

Two other links:
http://www.ceantar.org/Dicts/MB2/mb14.html#draoi
http://www.ceantar.org/Dicts/MB2/mb12.html#darach

Assuming we do go with Proto-Celtic *dru-wid as the basis of "druid",
would the above information suggest that PC kept both versions of the
IE word for "tree" (using them differently, of course)? And if so,
would would the actual PC roots and meanings for both be?