Are there any?
It’s all Greek to me…
Well, someone had to say it!
Seriously, Cornell University’s Uncle Ezra tackles this in Question #4 on the linked page.
Apparently, there is no one naming convention for Greek societies. The older frats/sors got their names from the Greek initials of their mottoes. The newer ones are either basically meaningless or come from Greek letter-equivalents to the initials of their English mottoes.