Usage patterns
陳腐な〈物〉a clichéd/hackneyed thing (idea, expression, metaphor, etc.)
His speech was full of clichéd expressions.
〈物〉が陳腐になるfor something to become stale/trite over time
That expression has become clichéd from overuse.
〈物〉に見えるto look/seem stale (used as 陳腐に見える)
The idea that once seemed groundbreaking now looks stale.
