Source: The Great Interpretation of Dreams (Ibn Sirin)
A bridle in a dream indicates religion and piety that restrain its owner from sins. It indicates authority and wealth.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
A bridle indicates a man who manages affairs. Whoever sees himself leading an animal with a bridle is leading a man.
Source: Signs in the Science of Expressions (Ibn Shaheen)
A bridle is interpreted as goodness and position.