A perishableproduct that is a day old, and may be sold more cheaply as a result.
2011, Donald Ray Pollock, Bactine / Giganthomachy / Pills:
The older woman waddled over and squeezed into a booth opposite the counter while the young one stood and ordered a big box of day-olds and two quarts of hot chocolate.
2007, W. Glasgow Phillips, The Royal Nonesuch, page 353:
Instead of trying to make her crowds quit throwing things, Audra had simply distributed items it would be okay for them to throw: day-old corn tortillas. A big bag of day-olds cost only a couple of bucks […]