Adjective > Stale
1 a : of food : no longer good or appealing : no longer fresh
stale food
stale bread
1 b : not clean, clear, or pure : having an unpleasant taste or smell
stale air/water
a room filled with stale smoke
2 : not interesting or new : boring or unoriginal
stale news/jokes
Their relationship went stale. (=became dull or predictable)
3 : not as strong, effective, or energetic as before
She felt stale (=bored) in her job.