Threadbare (adjective)

1. Worn through so that the threads show; frayed.
2. Extremely thin or worn, as from much use.

Origin:

From thread + bare, meaning worn out.

Examples:

1. The carpet was threadbare in the high-traffic areas.
2. His threadbare suit was a sign of his poverty.
3. The book's plot was threadbare and unoriginal.
4. The cloth napkins were threadbare and needed to be replaced.
5. She couldn't stand the threadbare excuse he gave for being late.