The adjective depleted describes something that's been used up. A stressed-out mother of four little kids might find her patience depleted after a crazed birthday party at the roller rink.
The word depleted comes from the Latin deplere, "to empty," or literally "to un-fill." You may have seen depleted shelves where bread and milk used to be if you visit a grocery store before a big snow storm. If you tend to get sick a lot, it may be because your immune system is depleted, or worn out, and a river can become depleted, or dried up, after a long drought.