1. worn so much that the threads show; frayed and thin from use
2. lacking in freshness or effectiveness due to overuse; hackneyed

Examples

• His threadbare jacket had holes at both elbows.
• The old sofa was threadbare from years of use.
• She wrapped herself in a threadbare blanket.
• The politician’s threadbare excuses fooled no one.
• His threadbare arguments failed to convince the jury.
• The carpet was threadbare in the high-traffic areas.
• Her threadbare coat provided little warmth in winter.