space cadet


: a flaky, lightheaded, or forgetful person

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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 On Michaels Under adult supervision, a little space cadet can create five colorful, rubbery planet models in just minutes using a spherical mold and polymer granules. Cheryl Fenton, Parents, 22 Nov. 2023 In Asteroid City, a space cadet convention in an American desert town in 1955 is disrupted by world-changing events. Tommy Cummings, Dallas News, 2 June 2023 But unfortunately for the space cadet, everyone else put on their best performances, too. Ree Hines, Forbes, 3 May 2023 Feel like a space cadet? USA TODAY, 17 Apr. 2023 And Affleck makes Knight a Zen-adjacent space cadet, all eager to quote Buddha. Bill Goodykoontz, The Arizona Republic, 3 Apr. 2023 While fans rejoice in a handsome space cadet, not all are happy with the changes to the original character. Vulture, 1 July 2022 Then Paul Rudd as Paris is a bit on the outside, and a bit of a space cadet, so an astronaut felt right. Liam Hess, Vogue, 2 Nov. 2021 Your high school English teacher might have called you a space cadet, but in reality, even the briefest mental vacations can restore a sense of well-being. New York Times, 10 Apr. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'space cadet.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1973, in the meaning defined above

Time Traveler
The first known use of space cadet was in 1973


Dictionary Entries Near space cadet

Cite this Entry

“Space cadet.” Dictionary, Merriam-Webster, Accessed 23 Apr. 2024.

Kids Definition

space cadet

: a person who is confused, forgetful, or very inattentive
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