[Verginius Rufus]

I was told that when Blegen went looking for the palace at Pylos, he asked himself, "if I was a Mycenaean prince, where would I put my palace?"...found a likely spot and immediately found the palace when they started digging.

Thalassa is one of many words with -ss- or -s- (including common nouns like glossa and nesos and proper nouns like Knossos, Tylissos, Parnassos, etc.--in Attica they tend to be -tt- as in Hymettos, Lycabettos) that are all thought to come from the pre-Greek population. The placenames are on the mainland, on Crete, and on other islands. Also words in -nth- are thought to come from the same previous language (Corinth, plinth, etc.).

For place names to be taken over from earlier inhabitants is common--many examples in the US of Indian, Spanish, or French place names.

[SunkenCiv]

-nth suffix means “place of”, for example “Corinth” means “place of the Carians”. :’)