space cadet


Definition of space cadet

: a flaky, lightheaded, or forgetful person

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Did You Know?

Space cadet has been used derogatorily since the late 1970s, but long before then it referred to the rank that the character Matt Dodson hoped to achieve in Robert Heinlein's 1948 novel Space Cadet. Other writers of futuristic fiction followed Heinlein's lead, using the word in reference to young astronauts. From there the meaning broadened to cover any space travel enthusiast. Today the word is occasionally used as a slang word for a pilot who shows off, but it most commonly refers to those of us who may seem to have our minds in outer space while our bodies remain earthbound.

Examples of space cadet in a Sentence

Don't be such a space cadet.
Recent Examples on the Web By wielding a giant sword and chanting a mantra, Adora changes from mumsy space cadet into a disco-interpretation of a goddess: gold go-go boots, matching golden gauntlets, a winged vaguely Nordic tiara, and a crimson cape. Alex Abad-santos, Vox, "She-Ra and the Princesses of Power honors and challenges the original She-Ra.," 21 Nov. 2018 Congress would have to authorize a new branch, but Members of both parties seem willing, albeit after a fight over whose district will host the space cadets. The Editorial Board, WSJ, "Houston, We Have a Space Force," 4 July 2018 Pep Bonus trivia: The Kellogg’s Pep box featured cardboard cutouts of a space cadet cap, gauntlets and a ray gun. Jennifer Rude Klett, Milwaukee Journal Sentinel, "Cereal trivia quiz: Test your knowledge," 20 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'space cadet.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of space cadet

1973, in the meaning defined above

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Time Traveler for space cadet

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The first known use of space cadet was in 1973

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Cite this Entry

“Space cadet.” Dictionary, Merriam-Webster, Accessed 27 Jan. 2021.

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More Definitions for space cadet

space cadet


English Language Learners Definition of space cadet

informal : a person who does not pay attention or who tends to forget things

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