adjective staler stal′er, stalest stal′·est

1. having lost freshness; made musty, dry, bad, etc. by having been kept too long; specif.,
   1. flat; vapid; tasteless stale beer
   2. hard and dry: said of bread, etc.
   3. low in oxygen content; stagnant stale air
2. having lost originality or newness; lacking in interest through familiarity or overuse; hackneyed; trite a stale joke, stale gossip
3. out of condition, ineffective, enervated, bored, etc. from either too much or too little activity
4. Law having lost legal force or effect through lack of use or action, as a claim or lien

Etymology: ME, prob. via Anglo-Norm < OFr estale, quiet, stagnant < Gmc *stall: for IE base see still

transitive verb, intransitive verb staled, staling stal′·ing