Hi. Cuiña, Cuíña (modern spelling), Cuña... derive from the medieval form Colina, frequent in Medieval charters, which would be ultimately a Vulgar form from Latin Collinus 'hilly'. But it's no easy to explain how the Latin geminate l was lost in Galician (we would expect **Coliña).
If I understand correctly Paulo Malvar assumes that Cuíña, etc, are diminutive formation, so I guess that he is thinking in something such as *conina > *cõĩa > coiña > cuíña/cuña (in parallel to local substrate word cauno > Medieval Galician *cõõ > Mo. Galician con 'rock' / coio 'pebble, stone'; cauneto > coído 'pebble beach'; in the evolution of Galician both /l/ and /n/ are lost when in between vowels, frequently causing later epenthesis of nasal consonants, or of anti-hiatical consonants or glides).
But the other Paulo, Paulo Martínez Lema, since Cuíña places are documented as Colina in Medieval documents, prefer to separate both family of words and defends that cuíña < (local) Vulgar Latin *colina < Latin collina. I would rather accept this interpretation because, well, documents.
PD: the aformentioned evolutions are similar to that that lead from Latin caulis, caulem 'cabbage' to modern Galician col and coia (but Portuguese couve).
Yes, but it doesn't exclude the other one. I mean both of them could exist. Sometimes, two different etymologies provide the same word (with different meaning). In other words, the etymology of some cuiñas maybe the one suggested by one Paulo and the etymology of other cuiñas may be the one suggested by the other Paulo.
Ah, yes, you're right. Just as an example, Galician coia 'cabbage' < Latin caulem, Galician coia 'stone (of a fruit)', from coio 'stone, pebble'. And in fact there are a number of minor places called Coiñedo, Coiñal, Coiñeira... where -edo, -al, -eira are suffixes that (for you and me rather obviously) confer the meaning of "rich in"... coiñ- is a now lost variant of coio 'pebble' / con 'rock' < cauno (coiñ- < *caunio?) < Celtic.
But the fact is that whilst colina is relatively common in local Medieval Latin charters (39 hits in CODOLGA), the aforementioned form are less common: there is a place name Caunoso mentioned in 954, agro de Cauneto in 974, senra de Cauno Alvo in 1009, well, and further Cauno, illo caunieto, Porto Caunioso, in Caunito, per Cauneto, villa de Cauneto. These form have originated today place names such as Coído (and Coiñedo), but none of then could have directly originated Cuíña.
Estudo etimológico, diacrónico e diatópico do topónimo Cunha (e variantes) by Paulo Malvar Fernández quotes that collina (double "l") in the sense of hill, came from Italian into Galicia in the 17th Century, sourcing this information from Coromines. Collina at first had a strict military use, Paulo says.
Now, suddenly, there are 39 colina hits in CODOLGA.
This makes me think if the colina mentioned in medieval documents means the same as the "Italian" collina mentioned by Paulo Marlvar. What is your opinion on this?
TL; DR: Cuíña < Colina is a sure thing, but I'm not sure of the meaning of the Medieval word or words colina. Certainly it's more interesting than what I was expecting
Well, the multi-volume "Diccionario crítico etimológico castellano e hispánico" is the place to go for the etymology of a Spanish or a Galician word. It was a great achievement, even more so when considering that Joan Coromines was an exile for a part of his life (thanks Franco; never again Franco; bye-bye Franco); but it is also as far as you can go without computers.
Also, most of the medieval Galician charters and documents, either in Latin or in Galician, that we can access now in the web (CODOLGA, GMH, Corpux Xelmirez and other corpora) have been edited and published during the last twenty or thirty years, so Coromines had no access to this material, which means that sometimes he made wrong assessments in reference to a given word. An example: he considered that the family of the word marco, marcar, demarcar…was a Germanism that came to Spanish from Italian… But in fact in Galician these are very common daily words which are well presents in local documents since the 9th century (we don't have many earlier documents), so they happen to be local Germanisms probably taken from the Suebi who settled here in the 5th century (as brétema, laverca, groba, meixengra, zapa, to cite some usual suspects).
So I guess that Coromines was not even aware of the presence of this word, colina, in Latin local documents.
As for its meaning, I'm not sure at all; most of the time is already a place name, any of today's Cuíña/Cuíñas. Examples:
“In Caldelas et Tibros Colinas et tercia parte de Baselisco. Sub urbe lucense Rapati. In nave fracta Eclesia Alba cum Agra Mala et pumares de Presares. In Bragantinos villa de Alio cum insula de Calion. In Celtigos de Reilon, et sexta de Pinario integra in Carnota. In Morracio Bellucio cum pumare de Mauron, et terras et pumares de Gienesto” 934
“alias adiunctiones nominatas -id sunt- Uilla Mediana. Colina cum familia sua. Argondi. Belsari.” 1071 ( → now Cuíña, Saa, Lugo, next to the villages called Argonde and Belesar)
It ins't easy, also, to get to the meaning of this word when used as an appellative. I would say that it refers to a vegetable garden or a seedbed, and in that case they are clearly related to Modern Galician coíña 'cabbage seed/sprout' < *colina ← Latin caulis; rather than to Latin collinus:
“de ipsa tercia vendimus vobis inde medietatem integra vinea, pumares, ceresales, perales, ipsa colina medietate, et de ipso lagare de tercia medietate integra, et de ipso agro per ubi est conclauso tercia media integra et de ipsa carrale tercia media ipsa vinea que comparavimus de Tanoi medietate integra” 885 (ipsa colina medietate: maybe here colina is a cabbage garden?)
“Et alia vinea ad casa de Gundemaro, levat se de illa colina et vai per succo de Daniel ipsa vinea cum suo conclauso” 975
In any case, cuíña today is just barely and locally attested as an appellative, meaning 'little hill'; while coíña is 'cabbage sprout'.
@Cossue thank you for the detailed reply and glad this raised your interest. In the older texts you listed, colina is written with one "l" only. This seems to confirm what Paulo states. After reading and re-reading your post, I agree with your reasoning.
" coiñ- is a now lost variant of coio 'pebble' / con 'rock' < cauno (coiñ- < *caunio?) < Celtic." The termination -ña remembers me the Celtic suffix -gno and -gna, which seems to mean diminutive: Celtic sheep = ouis but ouvigno is lamb. Cuin (probably meaning stone)> cuigna (small stone, pebble). Does this sound reasonable to you?
Since the palatal nasal has several possible origins in Galician, and the group /gn/ is one of them, it sounds plausible. Sadly, other origins are more common: /ny/, or a nasalized /e/ or /i/ (in particular, Galician suffix -iño- , a diminutive, originated from an older -ĩo- < -ino-).
But given that Coiñedo alternates with Couñedo, maybe both derive from an older *caunio -> Caunietum > Coiñedo/Couñedo.