noun;

1 aggressive behaviour usually in the context of football related disorder.

2 to experience difficulties

abbreviation of aggravation
1 John: "How did you get on at Spurs on Saturday?"

Dave: "We beat them again and had all the usual aggro with the 'Yids' outside."

2 John: "Why don't we just get the bus to Spurs from Finsbury Park"

Dave: "Because every time we do that we get marched down Seven Sisters Road like cunts and get loads of shit off the old bill. Fuck that, I don't need all that aggro."
by sooner_gooner July 11, 2009
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a term that has been used for decades by surfers and other water-headed types to describe someone who is overly and unesscessarily agressive, competitive, or assinine whilst in the water. prolonged exposure to the aggro can ruin even the best session, so "deal" with them immediately (read: choke with your leash then return to your state of zen-like calm once they are dead)
Watch out for those SoCal types, theyre aggro, they should stay in Cali where they fucking belong.
by East End Hui January 25, 2005
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In MMORPG's and MUD's, means that an NPC will attack pre-emptively, instead of only returning an attack.
"That new monster they put in the newbie area is aggro."
by Kenthar July 6, 2004
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n: aggro
v: aggroed

Short for aggrovated, aggrovation, whatever you think it stands for.

Attacking of a non-player character. Aggro is that NPC that you attacked and it will start attacking you.

Generally used in MMO's like EverQuest 2 and WarCraft, to name the most common ones.
Goddamn, I aggroed another mob with my AOE.
by excitation August 27, 2006
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60's British slang for aggravated and aggressive.

Today usually describes an RPG or real life male who's physically aggressive and is "picking a fight".
The football fans went aggro after the game because a referee red carded the player who made the winning goal.
by lattetown May 5, 2007
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In a MMORPG or MUD refers to a mob that will attack without being provoked. Can also be used to refer to actually being attacked by such a mob.
1. Watch out, those goblins are aggro!

2. Crap! I just got aggroed by a goblin!
by Vespasian August 24, 2005
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