H, or ecchi

The English use of "hentai" is more similar to the way the Japanese use the slang term エッチ (H, or ecchi), which refers to any sexually explicit content or behaviour. Ecchi is simply the spelling-out of the Japanese pronunciation of the letter H. The origins of this term are uncertain, but it may be a shortened form of hentai used as a polite codeword in the 1960s.

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