"Glass cannon" is a popular term in gaming (especially online-gaming), where it refers to a character class that has remarkable offensive power, but has low defense. Urban Dictionary also defines this as:

Refers to a person, weapon, or vehicle which has a high output, but a low defense, life, durability, etc. link

However, I failed to find any references other than the above one. "Glass cannon" actually sounds pretty intuitive, so one can guess the meaning even when hearing it for the first time.

Is this phrase generally recognized outside of the gaming world (i.e., could I use it in a general conversation and be understood), and if it is, what is its etymology?

  • 1
    Isn't the etymology pretty obvious? Then again obvious etymologies are often incorrect ;-) Commented Oct 9, 2012 at 10:09
  • @Joachim Sauer: I don't know how "obvious" the etymology is, but my guess is it's a variation of the boxer's glass jaw. I don't know any other idiomatic usage linking aggressive/powerful fighting abilities to the fragility of glass. Commented Oct 9, 2012 at 21:16
  • 2
    @FumbleFingers: except that a glass jaw is a weakness, and only a weakness. In glass cannon, the two words are contrasted: "glass" implies weakness, but "cannon" implies strength. So I don't think there's an etymological link to glass jaw, apart from both phrases happening to use the metaphor of a material known to be fragile.
    – Marthaª
    Commented Oct 9, 2012 at 21:49
  • @Marthaª: I think you're probably overanalysing the semantics. In the real world, it's often a brass cannon, so phonologically we're not far away. I can't think of any "aggressive" context for glass apart from the particularly unpleasant verb meaning to smash a pint glass into someone's face. But there's also a loose cannon, so clearly cannon can be modified in a variety of ways. Commented Oct 9, 2012 at 22:05
  • 2
    Real cannons (actual war types, not the fun ones that fit on a shelf at home) were never made of brass. Perhaps you are thinking of bronze? As a USMC artilleryman you can take my word for that or you can read here: en.wikipedia.org/wiki/…
    – KnightHawk
    Commented Jul 12, 2014 at 14:57

7 Answers 7


I'm not a gamer, and I've never heard the term before now.

As to whether or not I could deduce its meaning, that depends entirely on context.

A similar phrase that first springs to mind is loose cannon, which etymologically has little to do with a cannon's firepower, but more to do with the dangers of a unsecured cannon rolling around on the deck of a ship.

Idioms using the word glass can refer to fragility (as in glass cannon), but the word often connotes transparency as well. A glass ceiling is something that you know is there, even if you can't "see" it. However, glass ceilings aren't exactly known for being easy to break. In software, glass box testing (more commonly called white box testing) means that the testers can "see" the inner workings of the code when designing their test plans.

In short, I wouldn't count on people being able to figure out the meaning of the expression merely by examining the two words put together. That said, the phrase might still be decipherable in some contexts, depending on what other clues are present.

  • 3
    I'm a long-time gamer and I'm quite familiar with the term glass cannon, but when I first heard it I assumed that a "glass cannon" was a weapon/character/whatever prone to self-destruction, since a real cannon made of glass would likely be destroyed when subjected to the explosive force of gunpowder.
    – Marcus_33
    Commented Oct 9, 2012 at 14:55
  • 2
    What @Marcus_33 said: my first reaction to glass cannon was, "well, that wouldn't survive its first firing too well, would it?" I can sorta see the gaming interpretation once it's explained, but if I just met the phrase "in the wild", there would have to be a heck of a lot of context to prevent my brain from going to the "lots of glass shards flying around" image.
    – Marthaª
    Commented Oct 9, 2012 at 15:31

Outside of the gaming world it's not really used. However, it's a nice expression and I think it would be understood.

  • 1
    But, but, would a glass cannon not explode when used? Heh. I am a gamer, but the term was never my favorite.
    – nycynik
    Commented Jun 11, 2017 at 3:51

That reminds me of Diablo 3, where character class like, Demon Hunter / Wizard usually falls into this category. I don't really hear this word anywhere else except in the gaming world.

Another similar example would be Meat Shield, which is also very often used, which is opposite to the meaning of Glass Cannon.

  • 1
    And to complete the trifecta "suspicious-looking fellows in dresses standing in the back and waving their hands in the air".
    – Marcus_33
    Commented Oct 9, 2012 at 18:40

In my experience Glass Cannon is also a term used in Collectable Card Games (Magic the Gathering) where a combination deck will be totally unable to recover in cases where the combination is countered/disrupted.

In this sense where the combination succeeds it results in a game win and when it fails it is a certain loss as there is no way to recover.


I've heard several types of missiles called glass cannons, because inherently they have no defense factor.


It doesn't seem like it would have much application outside military environments, or games, where both offense and defense might be considered in the same sentence.

  • Thanks for your input. Do you think you could find some sources to back up your instinct that this is restricted to those contexts?
    – Dan Bron
    Commented Sep 28, 2015 at 21:14

Spiritually, a glass cannon would be as stated before, glass being weak as in a weak vessel or body, while a canon is strong, as in Cinderella's shoe: A weak vessel such as a character who has a stronger spirit to protect them. Cinderella was a good person, therefore she had a good spirit protecting her, God. On the other hand, a character such as a human isn't strong against a powerful beast, but would have supernatural or demonic power to protect them from stronger creatures. So Cinderella's fate became so in spite of her wicked family who tried to stop her from going to the ball.

  • This answer seems to have gone off on a bit of a tangent. Do you think you could tighten it up, and put more emphasis on how it answers the question?
    – user867
    Commented Mar 2, 2015 at 23:20

Not the answer you're looking for? Browse other questions tagged or ask your own question.