Related Clues:

• Talks too much
• Argon and xenon, e.g.
• Some cause laughter
• Atmospheric mix
• Aerostatics subject
• Some are noble
• They're in the atmosphere
• Krypton and oxygen, e.g.
• Exhausts, say
• Neon and hydrogen
• Some elements
• Neon and argon, for two (Var.)
• Helium and neon
• They're in the air
• They can cause tears or laughter