Related Clues:

• Common solvent
• Early anesthetic
• Heavens
• Pre-Novocain stuff
• It's a gas
• It's a knockout
• Pre-op inhalant, once
• What a knockout!
• Wild blue yonder
• Old anesthetic
• Preoperative delivery, once
• Part of the gasoline additive M.T.B.E.
• The heavens
• It's a gas?
• Inhalation anesthetic of old