adjective / verb
stale
STAYL/steɪl/
Having lost freshness through age or repetition.
The uncovered bread is stale, and its slices are hard.

Etymology
A fixed position probably suggested drink left standing until it cleared—a desirable quality. Applied to food, long keeping instead implied lost freshness, which extended figuratively to things that had lost their interest or appeal.
In context
outdoor wind pushes fresh air in and pulls stale air out.
More examples
- Opening the windows helps clear the stale air.
- His jokes grow stale after weeks of repetition.
- Without proper storage, bread stales before we finish it.
Forms
stale · staler · stalest · stales · staled · staling
staleness noun — The condition of having lost freshness.