11 Jul 2010
I think I finally got it. This etymology has eluded me for a while but with so much to look up I left it on the backburner, simmering like a spicy gumbo. Nonetheless, it frustrated me at every turn. In almost every book, there's always the same answer: "unknown origin". Worse yet, some lazy etymologists tack its origin on Etruscan without any substantiation whatsoever, often without even being qualified in this language, effectively explaining one mystery with another. How convenient. However, just last night, I had a brainwave and it all seems to have fallen into place. Here's what I believe to be the most optimal solution I can muster.
I dare say the name of 'Rome' was originally Umbrian, not Etruscan nor Latin: *Rūma. It would literally have meant '(Town of) flowing waters', from *rūmōn 'river; flowing water', a securely Indo-European formation built on the root *reu- 'to flow, to run (as of liquid)' and the derivational suffix *-mo-. When we gander at an ancient dialect map, we see that the ancestors of the Umbri probably covered the area of Etruria before the arrival of the Etruscans. It also helps that an ancient name for the Tiber, the river running into Rome, was Rumon according to Servius. I can find no possible, attested root in Etruscan at all to help us unlock its meaning nor has anyone else published anything convincing and competent to this effect, so an Etruscan origin seems the least likely in all of this.
When the Etruscans finally came, they would have adopted the Umbrian name, thus Etruscan *Ruma. Note that Etruscan has no phonemic long vowels. In fact, the Etruscan language has no phonemic contrast between u and o either. Therefore, probably being pronounced [ˈɾo.mə] (assuming u in open syllables was pronounced as high-back /o/), the early Latini would have adopted it as Rōma (its original meaning in Umbrian presumably lost or obscured at this point).
Further word associations, immaterial to the debate of Rome's etymology, such as the pun with Latin rumis 'teat' created the myth of the nursing she-wolf protecting the founding twins, Romulus and Remus. Sound good? Good.
 Gessman, The tongue of the Romans: Introduction to the history of Latin and the Romance languages (1970), p.8 (see link); Pulgram, The tongues of Italy: Prehistory and history (1958), p.256 (see link).
 Servius, Aeneas 8.63 (see link): "Nam hoc est Tiberini fluminis proprium, adeo ut ab antiquis Rumon dictus sit, quasi ripas ruminans et exedens."; Servius' passage is acknowledged in Partridge, Origins: An Etymological Dictionary of Modern English (1977), p.2809 (see link). The fact that the author claims "more likely from Etruscan Ruma, the name of an Etruscan clan" despite being comparatively much less secure, even after already elucidating a perfectly rational and sufficient origin through Rumon, is a puzzling but typical display of obscurum per obscurius that continues to irk me as a reader.