According to an online dictionary Paraskeni is the Modern Greek for Friday. How you get from there to Paraskevi I don't know. Somebody mistook a nu for a v perhaps. I don't know when the Greeks adopted the 7-day week or when the days of the week were given Greek names. Presumably Greek-speaking Jews in the Hellenistic period had a name for Friday, but I wouldn't know what it was.

Bingley

Bingley