Aggro as a term originated in MMO's, but its usage has spread considerably.
Originally it was coined to describe any creature who would attack you on sight.
So an "aggro" mob was one who would attack without being provoked, as opposed to one who wouldn't attack unless you attacked it first.
The related usages here are "aggro range" or "aggro radius" which is the distance at which the mob will attack, and "aggro chain" which is whether or not the mob will bring his friends along, even if they are outside of normal aggro range.
As the games evolved "aggro" became the state of being attacked.
If you were being attacked, you "had aggro", and if you did too much damage to something
and it started attacking you instead of someone else you "stole aggro".
If you did something stupid you could have "too much aggro" which meant too many things were drawn to attack you.
In your example, he's saying that the unit AI can be exploited because they don't chain aggro, so you can move into their aggro range, and individually "pull" them from their groups and eliminate them one at a time.
gaming.stackexchange.com/users/479/Satanicpuppy
It means that you move closer to enemy forces (may be slightly attack 'em) and move back.
If your opponent does not react properly then only couple of units will "aggro" and start moving to attack your units.
So you can easily pick them alone.
i.e. as terran you can aggro enemy to go into range of your tanks you can also check wiki .
Starcraft's AI uses distance and type of unit to determine what to attack.
gaming.stackexchange.com/users/3932/Meta
"Aggro" is a shorted form of aggravate, meaning to annoy someone or something so it will attack you.
gaming.stackexchange.com/users/73363/Gerry
Aggro basically means aggressive.
If you see or hear it in a game in reference to something
(ex. Juliet in Lollipop Chainsaw complaining that the zombies are being so aggro
) it just means that they're aggressive and will attack you.
gaming.stackexchange.com/users/37566/Nia Ariel
It is a shortened form of aggressive.
It describes monsters that will recklessly attack with no regards to their own defence.
This term is in Magic the Gathering, a popular TCG, it is a type of deck with cheap, fast creatures that have high attack but low defence to try kill the opponent as quickly as possible.
Aggro creatures are mainly in red.
Mono-Red decks and Red-White decks are commonly used as aggro decks.
gaming.stackexchange.com/users/74117/Oreo
"Aggro" is short for aggravate, instead of aggressive.
In short, aggressive is a state.
An enemy is aggressive towards all players, but who they attack is determined by their level of aggravation towards the different members of the player group.
Depending on the game, it can be affected by a number of factors such as DPS, abilities, or even healing allies.
Here are some sample sentences: "Don't aggro the boss until you clear the adds."
Aggravate makes more sense than aggressive in this context.
"Those enemies have a very large or small aggro radius."
Aggravation works better than aggressive or aggression, because mobs that trigger based on range are considered "aggressive" already.
"X DPS class out
aggro'd
the tank
, that's what caused the wipe."
It makes more sense that it means "X DPS caused the enemy more aggravation than the tank, thus causing the enemy to shift its focus.
"
gaming.stackexchange.com/users/221158/Jaster83
I have heard "aggro" said in commentaries in a few different contexts and I have no idea what it really means. I can figure out what the commentator means, but I don't understand that word.
What does "Aggro" mean?
gaming.stackexchange.com
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gaming.stackexchange.com/questions/17608
gaming.stackexchange.com/users/6774/tenfour
It is used to describe any creature that attacks on sight. It is the shortened form of aggravate, meaning aggressive.  In gaming, the word aggro, which generally  means aggression, is defined by the community in similar ways.
The community defines aggro either as aggravate or as aggressive.