It just means "wrinkle" or "fold." It works as a noun or a verb.
Apparently, there's a Fijian actress named Rimple Sumer.
It's a moderately common name, apparently, in some part of India. There are a lot of faces on the Google image search.
I like that it kind of feels "folded"; you can hear the sound of folding in the word a little. Just a little.
Okay, so this word is really not that cool. But maybe you didn't know it already?