What is the correct vowel quantity for words formed from sĭ̄gn-?

Question

My dictionary (Latinsk ordbok – latinsk–norsk, Cappelen, Oslo 2007) has for all instances of words with sĭ̄gn- a long ī, e.g.:

• īnsīgniō, 4.
• īnsīgnis, adj. m. komp. (sīgnum)
• īnsīgne, is, n.
• sīgnātē, adv
• Sīgnia, ae, f.
• sīgnifer, era, erum, m.
• sīgnificāns
• sīgnificātiō, ōnis, f.
• sīgnificō, 1.
• sīgnō, 1.
• sīgnum, nī, n.

However, Wiktionary, Cassell, Gaffiot and L&S all list these words with a short ĭ. Where is the error? Are both correct? I have some linguistic background, but not enough to deduce from the Wiktionary etymology listing how Proto-Italic *seknom < Proto-Indo-European *sek- or *sekʷ- would develop into either long or short ĭ̄. I can see /e/ being raised to /i/, and /k/ being voiced intervocalically, but the /kʷ/ has me baffled. Honestly, I cannot see how *sek can develop into sīg, except perhaps due to the natural tendency to lengthen nasal sounds, but given that every single entry is listed with a long ī in my dictionary, it is hardly a coincidence.

An explanation of which form is correct based on etymology would be much appreciated. Thank you!

Answer 1

Usually the root vowel in signum (Classical Latin) in historical linguistics is considered long, despite its etymology and its further development in the Romance languages; that being said, the jury is still out. As it is common in historical linguistics, there is no ironclad evidence and it's a matter of how you interpret the available data.

Traditionally, it was explained as quantitative lengthening or qualitative raising (the latter view is adopted by Weiss 2020: 142, a very old idea btw), which is believed to have happened in the following environment

V > V̄ / ɳn (Meiser 2010: 79).

Meiser 2010 explains the seeming contradiction between the epigraphic, etymological, and Romance data by claiming that this change did not happen in spoken Latin ("Umgangssprache"), see p. 61 and 79 ("Im Vulgärlatein ist die Dehnung unterblieben"); Sihler calls this "a local or socially restricted tendency" (pp. 76-77).

Leumann 1977 (§127), citing some interesting evidence from Diehl's Altlateinische Inschriften

• 44 Poublilia Turpilia Cn. uxor | hoce seignum pro Cn. filiod | Dianai donum dedit

  CIL I² 42 s. 389 XIV 4270 De 3234 (bronzetafel aus Nemi)

• 353 C. Tertaus P. [f.] | Ciamus | basim fac., sígnum st[a]. | ex s. c. coer.

  CIL I² 2096 a XI 4092 f (Otricoli)

• 217 uecos Supn(as) | Victorie Seinq. | dono dedet | lubs mereto.|| queistores | Sa. Magio St.f.,|Pac.Anaiedio St(ati f.)

  CIL I² 388 s. 408 IX 3849 Ri 98 D De 3814 (bei Trasaco am ufer des Fucinersees) 2 verschreibung fuer seiqn. = seign.? Ihm Rh. Mus. 57, 316

also cf. Weiss 2020: 142, and Lindsay 1894: 138-139 for some interesting ideas, Niedermann 1953: 72 "Les tentatives ... n'ont pas abouti jusqu'ici" (i.e. the jury is still out), or Sommer and Pfister 1977 "Die Verlängerung trat wohl nicht auf dem ganzen Sprachgebiet ein (so auch Buck, Cl R 15, 311 ff.); eine allgemein anerkannte Erklärung ist nicht gefunden" (100)

Wachter 1987 ("Altlateinische Inschriften") seems to propose the following: a long vowel in Old Latin SEIGNVM and a short vowel in Classical Latin signum, as reported in Sen 2015: 145, but I don't have Wachter 1987 at home, so I cannot easily check this myself.

As for the etymological dictionaries of Latin, de Vaan gives sīgnum (and it's not a typo in this case, it's his choice), so do Walde and Hofmann (Band II, s.v. sīgnum); however, Ernout and Meillet opted for signum.

Unsurprisingly, Meyer-Lübke prefers sĭgnum (it's his Romanische etymologische Wörterbuch, if you were wondering why)

Answer 2

I cited some relevant sources in my answer to Are vowels long before "gn"? Your dictionary is following a once-common view that held that words like this actually had a long vowel (not just a heavy syllable) before gn. I consider it a bad decision to use this quantity rather than a short vowel ĭ in a standardized modern reconstruction of Latin pronunciation—because the evidence is conflicting and it seems like a needless complication—but it's debatable whether one or the other is "incorrect". (Before reading Alex B.'s answer, I didn't realize that there are still scholars today who consider it preferable to mark sīgn- with a macron.¹)

There are inscriptional spellings that we would normally interpret as supporting a long vowel in Classical Latin (with i longa and the digraph ei). These devices are not totally unambiguous indicators of /iː/: they can occasionally be found marking vowels that we have reason to believe are short.² In addition, there is a passage in Priscian, now generally believed to be an interpolation, that appears to say that vowels before gn are long as a rule.

But aside from that, all of the evidence points to a short vowel: that's the expected outcome of raising of Proto-Italic short *e to Latin ĭ before the velar nasal [ŋ], and as Draconis says, we see the expected outcome of a short vowel in Italian segno as well as some other Romance words such as Portuguese senha or Romanian semn.

If an explanation seems necessary for the spellings with seign- and sIgn-, it has been proposed that it was possible (although presumably not universal) for the quality of the vowel in this context to approach close [i]. Assuming we accept the usual hypothesis that Classical Latin ĭ when followed by a consonant typically had a near-close quality [ɪ], the use of the quality [i] instead might cause the vowel to be misheard or reinterpreted as being more similar to long ī, which we are pretty sure was pronounced as [iː]. In English, a comparable perception that words traditionally transcribed with /ɪŋ/ such as pink and sing contain the "long e" sound of queen rather than the "short i" sound of kin is reported by some, but not all American speakers. However, I'm not sure how convincing the qualitative explanation of those spellings is, as I don't know of any parallel evidence that words containing -ing- or -inc-, which also have the velar nasal [ŋ] after the vowel, were prone to being spelled with i longa or ei.

1. Carl Darling Buck argued in 1901 against the then-prevalent practice of marking ī before -gn- in "The Quantity of Vowels before gn", The Classical Review Vol. 15, No. 6, pp. 311-314, available on JSTOR

2. "Standardisation and Variation in Latin Orthography and Morphology (100 BC – AD 100)", by Veronika Nikitina (2015) gives the following list of cases where ei appears to stand for ĭ: "seine in CIL I2 583 (line 58), ceinis in CIL VI 282 (line 28), seibi in CIL I2 1739" (page 51)

Answer 3

It was short. As you mention, it came from a short vowel in PIE, but the Romance descendants also show that it was short in at least Vulgar Latin: Italian segno < signum would instead be **signo < **sīgnum if it was long. Since both its ancestor and its descendant were short, I feel confident saying it was short in Classical as well.

Some dictionaries use macrons to mark syllable weight rather than vowel length, especially if they're intended for people working with poetry. I'm not sure if yours is one of these, but if it is, it's telling you that the first syllable is heavy (since it has a coda consonant), even though the vowel is short.