Michal asked about Polish
rivernames.
Southern Poland shares many hydronyms with
Illyria, Pannonia and the NW Balkans, e.g.:
Sawa
~ Sava/Sau (ancient Savus/Sauos).
Raba ~ Rába/Raab
(Arabo:n).
Mroga ~ Cz./G. Morava/March (Marus < Germanic
Maraha < *Margos)
~ Serb. Morava (Margos).
The southern rivernames cannot be Slavic
imports -- many of them are attested in ancient sources.
Western and northern Polish hydronyms often
resemble those found in northern Italy or along the Baltic-Adriatic
route, e.g.:
Notec'
(13c. Notes') ~ Venetic Natiso/Natissa
<
*nat-is- (near Aquileia),
cf.
Latin nato: 'float, flow'.
Wierzyca (12c. Verissa)
< *xwer- + -is-
cf.
Verona, Venetic Varamus (river),
German Wörsbach, Werse.
Uiaduas (the Oder in
Ptolemy) < *wi-adu-a-s
~
Venetic Aduas < *adu- 'watercourse'.
Outside Poland, the Elbe/Labe <
*albH- 'white' can be suspected of
having Italic connections
Some names have cognates in both Illyrian
and Venetian areas:
S'rem (town on the River
Warta, no Slavic etymology)
~ Illyrian
Sirmium (modern Srijem), Sarminium,
N Italian
Sermione (village), Sermenza
(river),
cf. Thracian
Sermios (river) < *ser-m-(j)o-
from *ser-
'flow'.
Still other names may be too old to be
assigned to a particular branch:
Drwe,ca <
*Dru-ont-ja: from *dreu- 'run' (also with *-nt-)
one of the most widespread IE
rivernames,
with cognates from the British Isles to
India,
also in
Italy (Truentus, a river in Picenum), but
*dreu-
is unattested in Germanic and Balto-Slavic
(except in rivernames, e.g. Drawa ~
Drava/Drau).
Bzura < Brzura <
*brju-r-a < *bHreu(h)-r/n-,
cf. Greek phrear, -atos 'well',
English burn < brunna
Such examples could be
multiplied.
Piotr