Greek "sala-"

Fellow listers,

I´ve been just watching for some time. I wasn´t going to write so
soon, but I think I must contribute to this topic.
In Portuguese we say "salmoura". Or "salmoira" - the "ou"/"oi"
variation is common in Portuguese. Other examples, with the most
common form first: "coisa"/"cousa" (thing), "touro"/"toiro" (bull).

According to my resources, "salmoura" comes from Greek "halmyris",
via Late Latin "salemoria".
"Halmyris" = "salt water", and it appears in "halmirólise", a Geology
term that means "decomposition of rocks under sea waters".

I´m not sure, since I don´t have any information to corroborate this
statement, but is it possible that word halmyris passed to Latin,
then came back to Greek with other loanwords in the Middle Ages
(like "porta", for instance?).

Best regards,
André (Sao Paulo, Brazil).

P.S. The preposition in Portuguese is written with an "m". So
it´s "em", not "en".