Armenia in Graeco-Roman sources. I will regularly add here various toponyms and names and their relation to Urartian and Armenian names.
This one is interesting because it is another piece of evidence of Armenian speakers in that region. Strabo calls lake Urmia Mantiene and...
There are also large lakes in Armenia; one the Mantiane,8 which word translated signifies Cyane, or Blue, the largest salt-water lake, it is said, after the Palus Mæotis, extending as far as (Media-) Atropatia.
It is quite obvious that Mantiene can't mean blue. So it definitely relates to Armenian name Kaputan. Which indeed means blue. Now one can argue that it could be also an Iranian term. That is possible but it was mostly Armenians who used the term Kaputan so Armenian intermediation is more likely.
The same remarks are made by the editors.
Then comes lake Van.
The next is Arsene,9 which is also called Thopitis. Its waters contain nitre, and are used for cleaning and fulling clothes. It is unfit by these qualities for drinking.
Thopitis (also Tospitis) is from Tosp but Arsene is puzzling.
Well not much if we remember the number of toponyms like Arṣuniuini [(A CITY)] near Van in Urartian texts.
It is quite possible that this name is related to later Artsruni on one side and to various toponyms that appear with the root Arts- in the nearby like Artsania the name of river Murad in old texts.