Nephelococcygia is a term used when people find familiar objects within the shape of a cloud. The word comes from the play "The Birds" by the Greek playwright Aristophanes. It is about an imaginary city built in the clouds by the birds at the instigation of two Athenians, and represented both as a fantastic caricature of Athens in the poet's day and as a sort of Philistine Utopia full of gross enjoyments.

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