What's the difference between jealousy and envy?
An honest distinction between two feelings that get conflated constantly — and why getting them right helps you understand what you are actually feeling.
You said you were jealous of your friend's promotion. Someone corrected you and said it was envy. You looked it up to see who was right, and the dictionary definitions made the distinction sound subtle to the point of pedantic. They both seem to be about wanting what someone else has. Why do we have two words? We have two words because the underlying experiences are actually different — different in what they are about, different in what they want, and different in what they signal about your relationship to the other person. Once you can tell them apart, you can name what you are feeling more precisely, and that precision matters because the right response to envy is different from the right response to jealousy.
Here is the actual distinction between jealousy and envy, in a way that will stick.
Envy is wanting what someone else has
Envy is the feeling of seeing someone else with something good — a promotion, a relationship, a life situation, a possession — and wanting that thing for yourself. It is two-person: you and the thing they have that you want. Envy is forward-looking and acquisitive. The desire is to have the thing. The feeling about the other person is usually mild — you are not really focused on them, you are focused on what they have. Sometimes envy comes with admiration; sometimes with resentment; sometimes with neither, just a quiet ache.
Jealousy is fearing the loss of what you already have
Jealousy is three-person, almost always. There is you, there is something or someone you have, and there is a third party you fear is taking it away. You are jealous of your partner's attention to someone else. You are jealous of a colleague who threatens your standing with the boss. You are jealous of your child's affection for a teacher. Jealousy is protective and defensive. It is about loss, not gain. The third party is the threat.
If there's no third party, it's probably envy
This is the simple test. Are you afraid of losing something you have to a specific other person? That is jealousy. Are you wishing you had something someone else has? That is envy. People say 'I am jealous' for both because the language is loose and because envy sounds slightly worse to admit. If you are tracking what you actually feel, the third-party test sorts almost every case correctly.
The right response to each is different
Envy is information about what you want. The healthy response is to ask whether the desire is genuine — whether you actually want the thing or just want what the thing represents — and then either pursue it deliberately or release it. Jealousy is information about a relationship under threat. The healthy response is to look at the relationship, ask whether the threat is real, and address what is actually going on in the connection rather than just resenting the third party. Treating envy as jealousy or vice versa leads to the wrong response.
Both feelings are normal and survivable
Neither feeling is a sign that something is wrong with you. Both are ancient, social emotions tied to status, attachment, and resource awareness. The problem is not having the feeling — it is being unable to name it accurately and therefore being unable to think about it clearly. The names exist for a reason. Use them precisely and the feelings become tractable.
There's a word for that. Find it.
Describe a feeling you cannot quite name — the messy emotional state, the bittersweet mix, the thing there should be a word for — and Name That Feeling finds the precise term. From common English words you forgot to obscure terms from German, Japanese, Portuguese, and Finnish that captured what English missed.