Fresh (non-salt) water is also called sweet in English. Surprisingly, the word sweet is also used in some Slavic languages.
To be precise:
- in Polish,
woda słodka
- in Czech,
sladká voda
- in Croatian (as well as in Serbian and Bosnian, may be with different spelling),
slatka voda
Also, there are some Slavic languages where literally питьевая
means "пресная" (it worth to mention that the same we can tell about above-mentioned languages, it's just that this expression are not 100% interchangeable)
For example, in Macedonian, питка вода
.
Though in Bulgarian, which is close relative of Macedonian, it is said прясна вода
. In Ukrainian one should say прісна вода
, in Belorussian, прэсная вада
. But the two last examples are not that surprising, since both Ukrainian and Belorussian belong to the same subbranch of Slavic languages that Russian belongs to as well.
The question is: Has it ever existed expression "cладкая вода" in Russian, with that very meaning. If yes, when and how it loose battle to "пресная вода"?
UPD: here is an excerpt from Church Slavonic dictionary:
сладкїй - cладкий; весьма приятный; добрый, кроткий.
This does not give any hint.