Source: The Great Interpretation of Dreams (Ibn Sirin)
The eunuch in a dream indicates angels. Whoever sees himself becoming a eunuch attains exaltation. It may indicate a man who does not keep a secret.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
The eunuch indicates a man trustworthy with secrets. Seeing him indicates goodness.
Source: Signs in the Science of Expressions (Ibn Shaheen)
The eunuch is interpreted as goodness. Whoever sees himself speaking to him will attain goodness.