Source: The Great Interpretation of Dreams (Ibn Sirin)
A nightingale in a dream is a singing child or an eloquent man.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
A nightingale indicates a righteous man. Its song indicates hearing good words.
Source: Signs in the Science of Expressions (Ibn Shaheen)
A nightingale is interpreted as goodness. Whoever sees himself hearing it will hear good news.