Miley Cyrus -- I’m Sooooo NOT Engaged

Yes, she wore a ring and yes, it was on her ring finger -- but Miley Cyrus still can’t figure out why everyone thought she was engaged ... because it ain't true!!!

As we reported, Miley was spotted with a giant rock on that special spot last Thursday -- sending the internet buzzing with rumors she's engaged to BF Liam Hemsworth.

But Miley quashed the gossip today tweeting, “I'm not engaged. I've worn this same ring on this finger since November!”