Why does "ῤάρος" have a smooth breathing?

Question

I recently discovered that LSJ lists exactly two words beginning with ῤ (rho with a smooth breathing mark): ῤάρος and its diminutive ῤάριον.

Most beginning Greek students are taught, of course, that all words beginning with rho should have a rough breathing (ῥ). LSJ has 957 results beginning in this way.

A few questions:

• How is this pronounced?
• Why did only this word get the privilege of having a smooth breathing?

And, since the LSJ entry is pretty opaque, I'd also like to know:

• What does ῤάρος mean?

Answer 1

I wasn't able to find out why this word, or name, has a smooth breathing.

As you may have seen already, LSJ actually has separate entries for "Raros", a name, and "raros", the "embryo" word that TKR's answer deals with. It's unclear to me if these have the same origin.

LSJ seems to have a bit more information and examples of words related to the name in its entry for "Rarion pedion":

the field
A. of Rarus, where tillage was first practised, and which was sacred to Demeter, Paus.1.38.6, St.Byz.; (without πεδίον) Ρ̓άριον, τό, h.Cer.450; Ρ̓αρία, ἡ (sc. γῆ), Plu.2.144b; whence the goddess was herself called Ρ̓αριάς, ἡ, St.Byz. [α is long, h.Cer. l.c., so that the accent is prob. not Ρ̓άρος, as in most codd.:—for the smooth breathing, v. Hdn.Gr.2.402, 940.]

Here is a relevant Quora post: Why is “ρ” translitered as “rh” instead of “r”? Philip Newton's answer cites a passage from Gaps in the System by Nick Nicholas:

rho with smooth breathing appears [...] in Ancient representations of psilotic dialects. The TLG corpus manages 57 instances, all of them Aeolic, with the exception of Rarus, father of Triptolemus, the first human to have been taught agriculture by Demeter; his name was apparently back-formed from the (non-Attic) Rarian field in Eleusis associated with the cult of Demeter. In the surviving corpus, Rarus and his field are predictably mentioned more by the grammarians, who loved a good exception, than by the classics themselves:

Τὸ ρ ἀρχόμενον λέξεως δασύνεσθαι θέλει, ῥά, ῥανίς, ῥάξ χωρὶς τοῦ Ρ̓ᾶρος (ἔστι δὲ ὄνομα κύριον) καὶ χωρὶς τῶν ἐξ αὐτοῦ οἷον «Ρ̓αρίδος Δηοῦς» καὶ Ρ̓αρία γῆ καὶ Ρ̓αριάς, σημαίνει δὲ τὴν Δήμητρα, καὶ Ρ̓άριον πεδίον ἐν Ἐλευσῖνι, ἐπὶ τούτων γάρ φασι τὸ μὲν πρῶτον ρ ψιλοῦσθαι, τὸ δὲ δεύτερον δασύνεσθαι. ἀλλὰ τὰ δύο ρρ ψιλωτέον ἐπὶ τούτων καὶ κατὰ τὴν πρώτην συλλαβὴν καὶ κατὰ τὴν δευτέραν. (Herodian, De prosodia catholica 3.1.547)

<p>At the beginning of a word, <em>r</em> takes a rough breathing, as in <em>rhá</em> "then", <em>rhanís</em> "drop", <em>rháx</em> "grape", except for <em>Rarus</em> (a proper name) and the words derived from it, such as "<em>Rarian</em> Demeter" and "<em>Rarian</em> earth" and <em>Rarias,</em> which is a name for Demeter, and the <em>Rarian</em> field in Eleusis. It is said that for these the first <em>r</em> has a smooth breathing and the second a rough; but the two <em>r</em>'s in these words should bear a smooth breathing both in the first and in the second syllable.</p>

Not all authorities put up with the exception; the Suda preferred to call Demeter Rharias.

I also found a short allusion to dialectal variation in the realization of rho in an extract from the book Asianic Elements in Greek Civilisation (1938), by William Ramsay, "Chapter XXI: General Principles", hosted by The Gifford Lectures online:

The letter “r” appears and disappears in perplexing fashion in Anatolian words as written in Greek alphabet. Probably a soft “r” was used in Asia Minor as in the English word pretty; but there were doubtless more sounds than one “rho” in Anatolian although they cannot now be distinguished. In Greek the “rho” was rougher and is written ῥ except in Aeolic (which is more Anatolian in type).

As far as I know, all modern dialects of Greek are psilotic; according to Wikipedia

The loss of /h/ happened at different times in different dialects of Greek. The eastern Ionic dialects, the Aeolic dialect of Lesbos, as well as the Doric dialects of Crete and Elis, were already psilotic at the beginning of their written record. In Attic, there was widespread variation in popular speech during the classical period, but the formal standard language retained /h/. This variation continued into the Hellenistic Koine. [...] By the late Roman and early Byzantine period, /h/ had been lost in all forms of the language.

So at later time periods at least, and in earlier time periods for some varieties of Greek, there would have been no difference in pronunciation between rho with a rough and smooth breathing. It would just have been a spelling exception to memorize.

Answer 2

To unpack the LSJ entry a little: the word is only found in grammatical works, and these differ as to its meaning:

• EM is the Etymologicum magnum, a 12th-century Byzantine lexicon/encyclopedia. This is online, and the entry can be seen here. It says that some people think ῤάρος is the name of a place, others think it's a synonym for γαστήρ "belly", and that the diminutive ῤάριον is derived from the latter sense and means "fetus" or "infant" (βρέφος). This edition doesn't show the breathing on the rho, unfortunately.
• The Suda (a 10th-century Byzantine encyclopedia) also lists the words. The entries are here, and read "ῥάριον· τὸ βρέφος" and "ῥάρον· ἰσχυρόν", i.e. ῥάριον means βρέφος (as in the EM) but ῥάρον means "strong". This edition shows a rough breathing on the rho.
• Hesychius and Photius also say ῥάρος means ἰσχυρός "strong". (I haven't tried to find these online.)
• There are two sources for the smooth breathing: "Sch. D.T." = a scholiast on the grammarian Dionysius Thrax; and "Lex. de Spir." = the Lexicon de spiritu or περὶ πνευμάτων, a Byzantine collation of grammatical information on breathings. I don't have ready access to either text, but maybe someone here can tell us what either says about the breathing in this word. As for the meaning, the former source says it is Aeolic for "embryo", while the latter says it means "aborted fetus". ETA: thanks to Alex B. for finding links to both texts. It looks like the περὶ πνευμάτων merely lists the word as an exception without further comment; the scholiast on Dionysius explains that it's an Aeolic word and that Aeolic uses smooth breathing where other dialects have rough breathing, i.e. is psilotic. (That Aeolic is psilotic in the sense of lacking initial [h-] is uncontroversial; that doesn't necessarily mean it should also be expected to voice initial [r-], which is what the smooth breathing would imply. I don't know if there's any evidence for whether [r-] was really voiced in Aeolic or other psilotic dialects.)