Sleep Whacking 

When a man is masturbating while asleep.

Example 1

Friends Wife - "Can I ask you a personal question regarding your friend?"
Husbands Friend - "Shoot!"
Friends Wife - "I caught my husband masturbating while he was asleep and I could not wake him up."
Husbands Friend - "Was he making Gorilla sounds?"
Friends Wife - "YES! YES HE WAS!
Husband friend - "What you witnessed was an art form known as SLEEP WHACKING, sleep whacking is multi-tasking at it's best."

Example 2
My buddy was telling me about his marital affair the other night. It involved him sleep whacking and it put him in the doghouse.

Sleep Whacking by deucebiggss1 March 9, 2014

sleepwacking 

Wacking off in your sleep. NOT a wet dream, because you are physically touching yourself. Sometimes happens simultaneously to sleepwalking.

Eww, Jeremy was sleepwacking in his mom's room last night.

sleepwacking by johnsq99 April 16, 2007

sleepwhacking 

The act of masturbating in one's sleep.

Teenager: Mom, can you wash my sheets? I had another wet dream.

Mom: God Dammit, have you been sleepwhacking AGAIN?

sleepwhacking by the dirty liberal July 27, 2009

Sleepwacking 

1.When you are exhausted, going in and out of sleep mode, but still masturbating
2.Boston pronunciation of “sleepwalking”

Although it had been a long day, I found myself sleepwacking late last night

Sleepwacking by Juxtaposin April 17, 2020