AC has 2 meanings
1. What does AC stand for in Dungeons & Dragons?

Armor class

In Dungeons & Dragons (DnD) and other RPGs, AC stands for "armor class." A player character's (PC) armor class determines how hard they are to hit in combat, and a Dungeon Master (DM) will often ask players what their AC is while attacking with non-player characters (NPCs). NPCs also have ACs, and players' attack rolls must either meet or beat an NPC's armor class to hit.

In the 5th Edition of D&D, each player character's base AC is 10. This base AC can be modified in a number of ways, including by armor, spells, and class-based abilities. Thankfully, online character sheets (such as those available through can now track players' armor classes for them, allowing them to focus on casting spells rather than calculating sums.


Okay, so the giant spider attacks with an attack roll of 16. Does that hit?
Yeah, my AC's only 15. How much damage do I take?

Related Slang


Updated October 20, 2020
2. What does AC stand for?

Air conditioning

An acronym that refers to the air cooling system in households and other buildings.


Can you turn the AC up? It's getting too hot in here.

Related Slang


Updated July 23, 2014

AC Definition by

This page explains what the acronym "AC" means. The various definitions, examples, and related terms listed above have been written and compiled by the team.

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