What does nocturnal emissions mean?

Nocturnal emissions, also known as wet dreams, are involuntary ejaculations of semen from the penis that occur during sleep. They are a normal part of sexual development in males and usually begin during puberty, but can occur throughout adulthood. Nocturnal emissions are usually triggered by sexual thoughts or dreams, but can also be caused by physical stimulation such as touching or masturbation. They are not a sign of any medical problem and do not require treatment.