In One Piece manga, young Luffy wears a shirt containing the word "jiken".
What does "jiken" mean in Japanese?
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In this context, jiken (事件) means "incident" or "case".
The full picture indicates tamago jiken which literally means "the egg incident" where a chick is killed due to the egg getting cracked.
There might not be any deeper meaning considering Oda's nature of humor.