Ideally a dog shows a lot of restraint when acting defensively. In many situations a dog may accomplish what is needed by just a stare and then escalating accordingly to a growl, snarl, snap at the air, a "hit" where the dog hits a competitor with his teeth but does not injure, and then escalating levels of bites that will cause injury before an all out fight or attack. Particularly, during resource guarding and normal dominance related conflicts we typically see appropriate restraint and minimal amount of aggression to resolve conflict. When there is obviously much more aggression than would be necessary for a situation we would say the dog is also "skipping steps in the aggression cycle".
Learn more about skipping steps in the aggression cycle and other forms of canine aggression here:
Classification of aggression types in dogs