Related Clues:

• Unreactive
• Out of practice
• Banal
• Overused, as a joke
• Blah
• Like chips that have been set out too long
• Like neon
• Like krypton or xenon
• Like argon
• Dead to the world
• Like neon or xenon
• Old-hat
• Not reacting
• Not merely sluggish
• Moth-eaten