Tried to see if that's a British thing to interpret it that way, but it's still the third meaning in the Oxford dictionary, after the two I mentioned. "Fiercely protective of one’s rights or possessions" is how it's defined. The other meanings still come first, and obviously get more use, so I still wonder if it's a regional thing that you interpret the word that way, but I do agree that it's yet another possible interpretation of what the OP meant.

It is the exact difference you would learn in English not that long ago (~15 years ago)

Being jealous used to be used as a word completely different in its own right. But it seems this usage is not used anymore which is strange to think.

Edit: In the actual learners section of the Oxford Dictionary it gives them in a different order. I am surprised you couldnt find any mention of the way I was saying, I literally couldnt find in a quick search another source except the dictionary that doesnt state how I said it as being correct. So it was seemingly very widely accepted (internationally) even if apparently now wrong.

Well, I went to my little Collins Gem English Dictionary from 1989, and it defines 'jealous' like this: 'distrustful of the faithfulness (of); envious; suspiciously watchful'.

My step dads from slightly earlier than that (81) doesnt mention envy at all or even like it. Just mentions about loved ones etc. Must have been changing over time in some way.

I have just been looking around myself.