What my friend was conveying is that envy is the want for something–usually that another has–and jealousy is the fear of losing something that one already has.
The interchangeable usage based on a vague understanding is just that (often normatively though they’re probably unaware of it).
iglou@programming.dev 1 hour ago
It’s not my definition. That is the subtle difference between the two words. But, most people use both words for the same thing, and most people only use the word jealousy for both things.