Related Clues:

• Lying, in a way
• Not up and about
• Not 1 Across
• Opposite of up
• Under cover, perhaps
• Sleeping, most likely
• Having hit the hay
• Like many of us at midnight
• In the Land of Nod
• All tucked in for the night
• In the hay, so to speak
• Sleeping in, say
• In the sack, slangily
• Reading by a night light, perhaps
• In for the night