Washed out cloth has become less bright as a result of being washed a lot.

She was wearing an old washed-out T-shirt and jeans. 她穿着洗得褪了色的旧短袖上衣和牛仔裤。

feeling or looking very tired

[ before noun ] I have to wearmake-up in the winter or I look completely washed out. 冬天我不得不化一点妆，否则看上去会十分憔悴。