Related Clues:

• About turn about the thing that puts one to sleep?
• What they give one in the theatre there
• There is the way to put one to sleep
• There one may be made to be unconscious
• The way to get 'er to go to sleep
• One in 23 across will put one to sleep like this
• There this can make one not all there
• Was said to fill the space and does put one under
• That's enough to put three to sleep
• It can be used as an anaesthetic
• Number no longer used?
• Cyberspace
• Fifth element, per Aristotle
• Old knockout agent
• Number Three at sea