Source: The Great Interpretation of Dreams (Ibn Sirin)
A wasp in a dream indicates a foolish, harmful man, or a highway robber enemy. Its sting indicates harm from an enemy.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
A wasp indicates a slandering man who corrupts relations between people. Killing it indicates triumph over an enemy.
Source: Signs in the Science of Expressions (Ibn Shaheen)
A wasp is interpreted as worry. Whoever sees one stinging him will be afflicted with worry.