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English

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Tongue-in-cheek

[edit]Adjective

tongue-in-cheek (comparative more tongue-in-cheek, superlative most tongue-in-cheek)

1. (idiomatic) not intended seriously; jocular or humorous
   

   He gave a tongue-in-cheek explanation of why the sky was blue, offering a theory about some primordial discount on light blue paint.

From Wiktionary.