tra·​jec·​to·​ry | \trə-ˈjek-t(ə-)rē \
plural trajectories

Definition of trajectory 

1 : the curve that a body (such as a planet or comet in its orbit or a rocket) describes in space

2 : a path, progression, or line of development resembling a physical trajectory an upward career trajectory

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Did You Know?

Formed with part of the prefix trans-, "across", trajectory means a "hurling across". By calculating the effect of gravity and other forces, the trajectory of an object launched into space at a known speed can be computed precisely. Missiles stand a chance of hitting their target only if their trajectory has been plotted accurately. The word is used most often in physics and engineering, but not always; we can also say, for example, that the trajectory of a whole life may be set in a person's youth, or that a new book traces the long trajectory of the French empire.

Examples of trajectory in a Sentence

the trajectory of the missile

Recent Examples on the Web

As clock speeds tended to top out at 4GHz to 5GHz, parallelism—originally in the form of support for more processor threads, and later to more physical cores—kept the processor performance on an upward trajectory. Mark Hachman, PCWorld, "Intel debuts 9th-generation Core chips, including Core i9 and X-series parts, with a few twists," 8 Oct. 2018 At the time, Tesla had 33,000 employees, suggesting that Tesla's headcount is still on an upward trajectory overall. Timothy B. Lee, Ars Technica, "Tesla lays off thousands of workers in corporate restructuring," 12 June 2018 India’s bilateral ties with the U.S. are on the upward trajectory. Vinay Kaura, Time, "Strategic Ties Between India and the U.S. Are Growing. But Russia Is a Stumbling Block," 11 June 2018 Now the United States and Iran are on an ever more dangerous trajectory that could create a new generation of ghosts. Robin Wright, The New Yorker, "The End of the Iran Deal and Trump’s New, Confrontational Foreign Policy," 13 May 2018 Countering the prosecution's argument that the bullet was fired from a distance, Carrington pointed out that testimony revealed the bullet was fired with an upward trajectory. Kim Chatelain,, "Jury convicts North Shore man in girlfriend's 'horrific' murder," 11 May 2018 With the prospect of moving into a new stadium next season and a top four place guaranteed, Pochettino took the time to acknowledge the collective efforts of the club this campaign as Spurs now look a side on an upward trajectory., "Mauricio Pochettino Challenges Tottenham to Win a Trophy After Kane Goal Seals UCL Spot Next Season," 10 May 2018 Many job guarantee advocates envision job guarantee jobs as exactly that: real public sector positions with the possibility of advancement and an upward career trajectory. Dylan Matthews, Vox, "4 big questions about job guarantees," 27 Apr. 2018 Her short but impressive career was already marked by an enviable upward trajectory. Alex Ritman, The Hollywood Reporter, "Hannah John-Kamen's Year of Blockbusters, From 'Tomb Raider' to 'Ready Player One'," 16 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'trajectory.' 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 trajectory

1696, in the meaning defined at sense 1

History and Etymology for trajectory

New Latin trajectoria, from feminine of trajectorius of passing, from Latin traicere to cause to cross, cross, from trans-, tra- trans- + jacere to throw — more at jet

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Statistics for trajectory

Last Updated

9 Dec 2018

Look-up Popularity

Time Traveler for trajectory

The first known use of trajectory was in 1696

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English Language Learners Definition of trajectory

: the curved path along which something (such as a rocket) moves through the air or through space

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More from Merriam-Webster on trajectory

Rhyming Dictionary: Words that rhyme with trajectory

Spanish Central: Translation of trajectory

Nglish: Translation of trajectory for Spanish Speakers

Britannica English: Translation of trajectory for Arabic Speakers

Comments on trajectory

What made you want to look up trajectory? Please tell us where you read or heard it (including the quote, if possible).


living or existing for a long time

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