there are attempts to reconstruct Dacian vocabulary
The Dacian language is poorly documented. Unlike for ancient Thracian, or Phrygian, there are no surviving inscriptions in the language.[citation needed] In ancient literary sources, the Dacian names for a number of medicinal plants and herbs survive in ancient texts.[3][4] that includes about 60 plants names with Dioscorides [5]. Some 100 Daco-Moesian placenames are documented and some 20 personal names.[citation needed][dubious – discuss]. Dacian language is also known through several hundred proper names [6], [7], about 900 toponyms [7], and one short inscription[6] [5].
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Both Georgiev and Duridanov use the comparative linguistic method to decipher ancient Thracian and Dacian names, respectively.
Georgiev argues that one can reliably decipher the meaning of an ancient place-name in an unknown language by comparing it to its successor-names and to cognate place-names and words in other IE languages, both ancient and modern. Georgiev considers decipherment by analysis of root-words(Wurzeletymologien) to be "devoid of scientific value".[29] He gives several examples of his methodology, of which one is partly reproduced here:
The town and river (a tributary of the Danube) in eastern Romania called Cernavodă. In Slavic, the name means "black water". The same town in antiquity was known as Άξίοπα (Axiopa) or Άξιούπολις (Axioupolis) and its river as the Άξιος (Axios). The working assumption is, therefore, that Axiopa means "black water" in Dacian. According to the known rules of formation of IE composite words, this breaks down as axi = "black" and opa or upa = "water" in Dacian (the -polis element is ignored, as it is a Greek suffix meaning "city"). The assumption is then validated by examining cognate placenames. The axi element is validated by another Danube tributary called the Axios, which is today known as Crna reka ("black river") and by the older Greek name for the Black sea, Άξεινος πόντος (Axeinos pontos, later altered to the euphemism Euxeinos pontos = "Hospitable sea"). The opa/upa element is validated by the Lithuanian cognate upė ("water") an by the Romanian cognate apă ("water").[30] (N.B. This etymology was questioned by Russu: Axiopa, a name attested only in Procopius' De Aedificiis, may be a corrupt form of Axiopolis).[31]
http://en.wikipedia.org/wiki/Dacian_language
some of reconstructed words
1) *aba, apa[14] water, river *ab- ("water", "river")
ok, this is about river names....
Slavic ending for river is often -ava
example in ex Yugoslavia Morava, Drava, Sava, Tamnava, Mlava....
thus, 1/1
2) *akmon[17] stone, rock
Slavic kamen = stone, rock
thus, 2/2
3)
*alda (noun),
*alta- (adj.)[21] swamp, waterlogged
I would say this is bad reconstruction as in Illyrian there is
alt = stream
Slavic liti = to flow
thus, 3/3
3/4 *alm- to flow, to stream RN Almus - no match
3/5 *amalas mistletoe PN Amlaidina - no match
3/6 *auras water RN Αύρας - no match
3/7 *axi- black PN Άξίοπα - no match
4/8 *baidas frightening, repulsive - bojati se (to be afraid)
4.5/9 *bal warrior bojnik / vojnik
5/10 *balas,*balos[24] strong [24] *bel ('strong')[24], - balast = carried weight
6/11 *balas white belo
7/12 *berza birch-tree breza
7/13 *bur, buris[28]
7/14 *brukla[29] cranberry
7/15 *buta(s)[31] house, hut, dwelling
8/16 *čuk-[34] peak, summit *ḱu- ("sharp", "pike") čuka = peak
8.5/17 *daba character, nature dobar = good natured
9.5/18 *dava city, fortress tvrdjava = tvrd (hard/solid/strong) + dava = fortress
9.5 / 19 *degis burning, shining PRN Degis
9.5 / 20 *dina place, area, plain PN Amlai-dina
this is Celtic ending!!
10.5/21 *dikas brave or strong, mighty dika = person we are proud of
10.5/22 *dita(s)[38] light (noun), bright (adj.)
11.5 /23 *drasda thrush (bird) drozd
12/24 *dribas, *drigas[40] wild, restless dripac - punk, corrupt person
12/25 *duia[43] swamp or mist, drizzle
13/26 *dumas dark brown tama = darkness
13/27 *galtis sheet-ice, frost
13/28 *genukla[45] pasture, meadow
13/29 *geras[47] good (-natured), kind
13/30 *germas hot, warm PN Γέρμαζα
13/31 *gilus[49] deep
14/32 *gira (giria) forest or mountain gora = mountain
14/33 *granda[51] plank
14/34 *griva[53] river-bed or river-mouth
14/35 kaga[55] sacred, holy
15/36 *kalas catfish? karaš
15/37 *kapas hill, slope
16/38 *karpa to cut, stone [58] krpiti = to sew, to put together
17/39 *karsa cave kras = carst
18/40 *katas stall, animal enclosure, fish-basin katun = shepards temporary house in hills
18/41 *keda chair, stool
19/42 *kerba swampy ground čorba = thick soup
19/43 *kerna bush
19/44 *kerta clearing in a wood
19/45 *kina dry place in a swamp
19/46 *klevas maple-tree PN Clevora
19/47 *krata swampy place or pile, heap
19/48 *kurta grove, glade
20/49 *lug- swamp, morass lug = grove
20/50 *maska pool, puddle
20/51 *medeka glade, small wood
20/52 *musas mould, moss
20/53 *nara(s) river, brook
20/54 *pala, *palma swamp, bog
21/55 *pil- to flow ploviti = to sail, to float
21/56 *preida pine-tree
21/57 *put- to swell, thicken
21/58 *ramus peaceful, restful - mir = peace
21/59 *rō(u)ka drizzle, fine rain
21/60 *rus- to flow
21/61 *san-apa confluence (of two rivers)
22/62 *sausas dry suvo = dry, suša = dry period
22/63 *sermas river, river-current
22/64 *skabas sharp, quick, lively
22/65 *skaudus painful, sad or powerful
22/66 *skuia fir-tree
22/67 *skumbras hill, down
23/68 *spirus fast, quick, rapid brzo
24/69 *stendas stiff, rigid, viscose stena =rock
24/70 *suka tear (ripped), gap
24/71 *suras salty
24/72 *taras chatterer, gossiper
25/73- *tauta people, nation, country četa = group of people (forming military unit)
25/74 *tiras bare, barren, desolate
26/75 *tut- blow, smoke duvati
26/76 *upa river
26/77 *urda stream, brook
26/78 *vaigas fast, rapid
27/79 *varpa whirlpool vir
27/80 *visas fertile, fruitful
28/81 *zalmo- fur, skin, shield šlem = helmet
28/82 *zelmas shoot (of a plant) zemlja = ground
28/83 *zud-as careful, precise
29/84 *zuras hot, shining zora = dawn
29/85 *zuv- fish
conclusion is that reconstructed Dacian words are much closer to proto-Slavic than Thracian words...
but still quite far away for continuity....
though we should keep in mind that this is reconstructed vocabulary....
but we do not really expect Dacians to be proto-Slavic
as Dacians map to earlier eastern linear pottery, while Slavic people map to earlier western linear pottery...
proto-Slavic would be Triballians in Moesia part of Danube flow, Pannonians in Pannonia and Veneti around Vistula and in Noricum... also Sarmatian Venedi (probably same as Antes) would be among Veneti
all these would be dominantly I2a2 people, perhaps with M458 R1a admixture