Stieg Larsson's Linguistic Riddle

I just finished reading Stieg Larsson's The Girl Who Kicked the Hornets Nest and I was intrigued by the linguistic riddle regarding the word "Amazon" that he presented on page 147 of the hardcover edition. While I realize the book is a work of fiction, there does seem to be some linguistic validity to this "riddle".

The riddle, according to Larsson, is whether the prefix "a-" means "without" in Greek or whether it means the opposite, "with".

In other words, is an Amazon a female warrior with or without breast?

Classic Greek mythology presents the tradition of Amazons destroying the right breast so as not to interfere with the use of the bow; however Larsson's book claims it has also been suggested that "an Amazon was a woman with especially large breasts."

Here is the relevant part of the entry for "Amazon" from an on-line edition of the Oxford English Dictionary (accessed through a private account):

1. pl. A race of female warriors alleged by Herodotus, etc. to exist in Scythia.
1398 TREVISA Barth. De P.R. XV. xii. (1495) 492 They were callyd Amazones, that is vnderstonde wythout breste.

And the etymology:

[a. L. Amazon, a. Gr. ,*****; explained by the Greeks from * priv. + ***** a breast (in connexion with the fable that they destroyed the right breast so as not to interfere with the use of the bow), but prob. pop. etym. of an unknown foreign word.] (asterisks indicate unavailable font)

However, considering that there is no record of Amazons being without a right breast in works of art and all of the available images of Amazon warriors on a Google image search show women with both breasts, I have to believe that one of the other proposed etymologies for the word is more accurate.

According to Wikipedia, there is an alternate Greek derivation from *ṇ-mṇ-gw-jon-es, meaning "manless, without husbands" or it could be derived from the Iranian ethnonym *ha-mazan-, meaning "warriors".