Dog
Quick Answer
Usually represents a weak enemy, a foolish person, or an oppressive ruler.
Classical Interpretation (Ibn Sirin)
A dog in a dream often symbolizes a weak but foolish enemy who is loud but coward. A dog barking at the dreamer indicates hearing terrible words from an ignorant person. Being bitten by a dog signifies harm from an enemy. However, a hunting dog or a guard dog represents protection, profit, and gaining authority.
Quranic Context
"And you would think them awake, while they were asleep... and their dog stretched his forelegs at the entrance. (Quran 18:18) - Denoting protection."