What Does Armor Digivolving Mean?

Armor Digivolving means Digivolving with a Crest or Digi Egg. I am not sure Crests can make any kind of Digimon Evolve, but Digi Eggs can. If you have seen Digimon then you probably have seen a Digimon Armor Digivolve. When Armor Digivolving is happening,  the armor from the Digi Egg goes on to the Digimon that is Armor Digivolving. But you have to have a Digi Egg that can fuse with the Digimon or else it will not work.

Here is a picture of a Digimon before Armor Digivolving.

Here is a picture of a Digimon that Armor Digivolved.