Just (adverb)

1. Exactly, precisely.
2. Very recently.
3. Only a moment ago.
4. Simply, only.
5. Morally correct, fair.
6. Used to indicate that a particular situation is happening and that there is no reason to be surprised or concerned.

Origin:

Middle english: from old french juste, from latin justus, from jus 'law, right'.

Examples:

1. I just finished my homework.
2. I saw her just a minute ago.
3. I just want to be alone.
4. I'm just trying to help.
5. That's not just, it's unfair.
6. It's just a small scratch.