On TikTok, the meaning of YN's usually "Young Nigga Syndrome" or "You are not serious" depending on the reference. Now, more popular and extensive use is "you are not serious", response video, memes, or fun, used to show distrust or mockery. Creators use it in captions, comments, or in skits when someone says or does something wild. It helps to add a dramatic or comical nature and increases the commitment through forwarding and trending slang.

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