Salty
Etymology
Rooted in African American Vernacular English, where “salty” for angry or upset spread widely online in the 2010s, especially in gaming. It rests on older American slang in which “salty” meant aggressive or irritable, distinct from the nautical “salty” for a seasoned sailor.
adjective · /SAWL-tee/
Bitter or resentful over something minor — visibly sore in a way that’s a bit out of proportion.
What it names
It names petty, lingering irritation, the mood of someone who lost a small stake and can’t stop grumbling about it. The word is gently mocking: to call someone salty is to note that their bitterness is showing and isn’t really warranted.
Example
He’s still salty that they didn’t pick his playlist for the road trip.
Related idea
Lighter than bitter: bitterness can be deep and lasting, while salty is smaller, pettier, and usually short-lived.