motorboat pillows

To fall asleep so hard that you bury your face between two pillows. This often leads to some snoring and making the sound of a motorboat. This could also mean that you are so tired that the desire to sleep is just as large of a drive as your sex drive. You would rather do both motorboat and sleep, so you choose to motorboat some pillows.

Man I can't keep my eyes open! I am staring at the bed trying not to motorboat pillows.