somniloquism

pronunciation:  som-nil-uh-kwizm

definition:  speech uttered in one's sleep.

My husband often entertains me, and sometimes scares the wits out of me, with his impromptu somniloquies.  He startled me awake early one morning with a sharp, "Shh!" 

I jumped out of bed and cried, "What?" 

"Quiet!  I'm on the phone!" he mumbled in his sleep.

I climbed back into bed and decided to be nosey, "Who are you talking to?" 

"Just.  A.  Minute!" he whispered, "let me finish this call."

I was tired and afraid to provoke him by further interrupting his important "call," so I went back to sleep.

Perhaps you live with your own gifted somniloquist?