Seeing a hornet in your dream signifies that you may face some dangerous or hostile situations in your life. It represents someone who is fighting against you or wishes to harm you. Additionally, it could symbolize a person who is earning through dishonest means or is untrustworthy towards you. The presence of the hornet can also be a symbol of your creativity and constructive power, indicating that you are on the verge of building something new in your life.
From Imam Muhammad Ibn Seerin's Dictionary of Dreams According to Islamic Inner Traditions â entry "Hornet" (page 213).
A hornet in a dream represents a fighting enemy, a builder, an architect, a thief, a highway robber, a despicable person whose earnings are unlawful, a singer who sings in the wrong key, eating poisonous food, or disclosing some thing. A hornet in a dream also represents a slanderer, a troublemaker, a strong fighter, a strong enemy that will argue against the truth, or merciless people, a vile person, a blood thirsty person, a stinging personality, or a harmful connection. Fighting attacking hornets in a dream means a war with evil people.
Note: Islamic dream interpretation depends on the dreamer's circumstances and state. This is a general guide drawn directly from the source book.