:) Yes, but the French, being realistic, call them what they mostly use them for: parapluie. Though come to think of it, I guess 'umbrella' is just as optimistic as 'parasol', only slightly less obvious about it - it must derive from 'something which provides shade'. How odd...
That is true that it's odd that Polish uses "parasol" for the device that protects you from rain, despite the etymology... but well, we just do ;) The big ones protecting you from sun are "parasol" as well.
"parapluj" used to be a word, but it has completely gone out of usage, so if you say it to a Polish person it's quite likely they won't have a clue what you mean, at least unless they know French.