I have no argument with the meaning of “aguadal”. I am asking for a cite saying Guadalcanal is derived from that because you said
Ok, where does the RAE say Guadalcanal is derived from “aguadal”? You cannot assume two words which sound alike have the same root because then we could say that he who assumes is an ass. Does “assume” derive from “ass”?
I am not saying it is impossible but I would be very surprised if the RAE said the ethimology of Guadalcanal is from aguadal and that is why I am asking for a cite. If you found it online please give us a link. If you have the book please cite literally.
BTW, aguadal is pretty much a dead word in Spanish. A google search produced under 50 hits and none of them use the word in the common sense, they are mainly proper names.