lacking originality or freshness; stale, hackneyed, or clichéd (often used for expressions, ideas, etc.).
その映画のプロットは陳腐で、最後まであまり感動しなかった。
The movie's plot was clichéd, and I wasn't very moved until the end.
陳腐な表現を避けて、自分の言葉で書くように心がけている。
I try to avoid hackneyed expressions and write in my own words.
彼の冗談はいつも陳腐で、同僚はあまり笑わない。
His jokes are always stale, and his colleagues don't laugh much.