No longer fresh and pleasant to eat; hard, musty, or dry. The bread was stale after being left out for several days.
No longer new and interesting; dull or unoriginal. The comedian's jokes were stale, having been heard many times before.
No longer legally valid or acceptable because of the passage of time, especially of a cheque, claim, or legal action. The bank refused to honour the stale cheque.
No longer energetic or in peak physical or mental condition; tired or jaded from overexertion or overexposure. After months of nonstop training, the runner felt stale and lacked his usual speed.
Of air, a room, smoke, or a smell: unpleasant because of being stagnant or no longer fresh. After hours with the windows closed, the office felt hot and stale.