Acronym pleonasm?
I've also heard "redundonym". That one sounds nice, doesn't it?
Here's another one: RAM memory.
BTW, some of these ARE indeed acronyms, for they're pronounced as one word, e.g. "PIN", "AIDS", "SAT".
The only "initialism" (that's the word for it) I can see here is "ATM", because each of the letters this word has must be pronounced individually.
Regards,
Mara.
Just one more thing:
"In 1997 the College Board, the company that administers the exam, announced that "SAT is not an initialism.[. . .] The SAT has become the trademark; it doesn't stand for anything."
Interesting, uh?