space cadet


Definition of space cadet

: a flaky, lightheaded, or forgetful person

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 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 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, 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, 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, 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.

First Known Use of space cadet

1973, in the meaning defined above

Learn More About space cadet

Time Traveler for space cadet

Time Traveler

The first known use of space cadet was in 1973

See more words from the same year

Listen to Our Podcast About space cadet

Dictionary Entries Near space cadet


space cadet

space charge

See More Nearby Entries 

Statistics for space cadet

Cite this Entry

“Space cadet.” Dictionary, Merriam-Webster, Accessed 20 May. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon


Test Your Vocabulary

Great Words for Scrabble

  • scrabble tiles that read scrabble quiz
  • Which of the following Q-without-U words means the number five in cards or dice?
True or False

Test your knowledge - and maybe learn something along the way.

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!