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?