Moonbat

Moonbat is a pejorative political epithet used in United States politics, referring to liberals, progressives, or leftists.

Descriptions of bat-like people on the Moon were part of the 1835 Great Moon Hoax.

A long poem The Proving of Gennad: A Mythological Romance by Landred Lewis (1890) uses the term "moonbat" to refer to unsound ideas, but not specifically political ones.

The term was used by science fiction author Robert A. Heinlein in a 1947 short story "Space Jockey" as the name of a rocket spacecraft used for the third step of a journey from the Earth to the Moon.

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