Source: The Great Interpretation of Dreams (Ibn Sirin)
The hijab in a dream for a woman is covering and a righteous husband. Taking it off indicates separation from the husband or exposure.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
The hijab indicates religion and piety. Wearing it indicates guidance.
Source: Signs in the Science of Expressions (Ibn Shaheen)
The hijab is interpreted as covering. Whoever sees himself wearing it, God will cover his flaws.