Media as a plural noun – Originally, the Latin singular used in English is “medium,” and the plural is “media.”
Nowadays common usage prefers “media” as a singular noun, although it is still recommended to use it as a plural noun in educated written style. After all, your work may be graded by a stickler, so don’t take a chance.
One of us predicts that “the media are” will soon die out (even in academic circles), at least if these searches mean anything:
“social media are” – c. 1 million hits
“social media is” – c. 27 million hits
In any case, the form “medias” is not normally used by normal people.
Jason Blake and Monika Kavalir