Aggro
Etymology
A clipping of aggravation (or aggression), British and Australian slang from the 1960s–70s for aggressive trouble-making. It gained a second life in multiplayer role-playing games, where "aggro" is the enemy attention a player generates, and "pulling aggro" means drawing that hostility.
adjective · /AG-roh/
Aggressive and spoiling for conflict; also, in gaming, the hostile attention a player draws from enemies.
What it names
As a mood word it names a person who is bristling, combative, looking for a fight. As a game mechanic it names a measurable thing — the "threat" that makes enemies target you — which is why players speak of "pulling aggro" or "holding aggro," a handy metaphor for becoming the focus of hostility in any group.
Example
He came into the meeting so aggro that everyone braced for a fight before he’d even sat down.
Related idea
Stronger than merely irritable: aggro is outward-facing and confrontational, actively seeking a target rather than just being on edge.