
So what does it mean for it to be called a misaligned error? When the machine is set up to strike coins, the hammer die is adjustable. The anvil die is fixed. So if the die is not centered exactly over the reverse die, the coin will look off center on just one side of the coin. These are normally not collectables as the devices don't fall over the rim. But when the devices do fall over the rim, they are collectable. They will look something like this:

Note the obverse die is off center, the reverse is not. They are called MAD coins. (Mis-Aligned-Dies) They are collectable when the letters fall over the edge of the coin. Again look at the obverse side, you can see what I'm talking about. Here is a wider shot of the coin:

See the motto is affected? When the die is run in the machine for an extened time, alters the die and wears off the edge of the die and creates a different type of error called die attrition. Here is a coin that is suffering that issue on the die that struck it:


The die that struck your coin will probably not progress to be damaged like this as it is a minor error. (just slightly off center) But if any die is further off centered, then it could be damaged, because of the lack of centering the die before the machine started the run of coins.
(To read more about die attrition, check out this site:
http://www.error-ref.com/?s=die+attrition )
Hope this helps.