Source: The Great Interpretation of Dreams (Ibn Sirin)
(By analogy with planets and meteors) A comet in a dream may indicate a great event, strife, the appearance of heresy, or the death of a great man with followers.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
(By analogy) It may indicate a warning of a major event, or indicate a man of impact and influence.
Source: Signs in the Science of Expressions (Ibn Shaheen)
(By analogy) It is interpreted as worry and fear of a great impending event.