have passed (someone's or something's) sell-by date

1. Literally, to be past the date by which an edible item should be sold before it spoils. That milk has definitely passed its sell-by date—it's curdled! Do not touch that chicken! It's passed its sell-by date, I'm just waiting till trash day to get rid of it. A: "Ew, that does not smell good at all." B: "Yeah, it's passed its sell-by date."

2. By extension, to be past the peak of one's abilities or career. The company is forcing my mother to retire because they think she has passed her sell-by date. That player has definitely passed his sell-by date—he hasn't had a good season in years. After I work out now, I'm sore for days afterward, which is an unpleasant reminder that I've passed my sell-by date.

have passed your sell-by date

BRITISH

COMMON If someone or something has passed their sell-by date, they are no longer useful, successful, or relevant. Do you think our marriage has passed its sell-by date? Note: You can also say that someone or something is past their sell-by date. Many people feel the presenter is past her sell-by date. Note: You can also say that someone or something has reached their sell-by date. Critics of the monarchy say it has reached its sell-by date. Note: Most food has a date stamped on its packaging: this is its sell-by date. After this date it is no longer fresh enough to sell.