tra·​jec·​to·​ry | \ trə-ˈjek-t(ə-)rē How to pronounce trajectory (audio) \
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

If Pioneer’s wells produce for 50 years and decline at 5% annually, its current production trajectory would still be nearly 12% below the company’s forecast of 849,000 barrels of oil and gas in the Permian, according to the Journal’s analysis. Bradley Olson, WSJ, "Fracking’s Secret Problem—Oil Wells Aren’t Producing as Much as Forecast," 2 Jan. 2019 Fun fact: Webb auditioned for Haddish’s role in Girl’s Trip, the one that put Haddish on her current trajectory as one of the most in-demand women in comedy., "Bresha Webb On Black Women In Comedy & Why She’ll Never Be Like Tiffany Haddish," 28 June 2018 If Sisco continues on his current trajectory, the end game of this early-season platoon might become clear quickly. Jon Meoli,, "Orioles catcher Chance Sisco making most of consistent starts, has best defensive day of career," 21 Apr. 2018 The models looked at how populations might shift in the future if greenhouse gas emissions abate, and compared that scenario with what could happen if emissions continue on their current trajectory. Andrea Thompson, Scientific American, "Wave of Climate Migration Looms, but It “Doesn't Have to Be a Crisis”," 23 Mar. 2018 While nations have committed to reducing emissions, this scenario would reflect a continuation of our current trajectory. John Timmer, Ars Technica, "When will the US feel the heat of global warming?," 20 Mar. 2018 Continuing on their current trajectory is likely to lead to greater isolation on their part, a situation which is not in anyone’s interest. Washington Post Staff, Washington Post, "Tillerson emphasizes allies in first remarks since firing but doesn’t mention Trump," 13 Mar. 2018 Indeed, on the current trajectory, his influence and tenure may be on par with those of the emperors of China’s historic past. Therese Shaheen, National Review, "The Digital Emperor of China’s Surveillance State," 25 Jan. 2018 The homemade rockets, aimed at Israeli border towns, had an irregular trajectory and sometimes landed inside Gaza. Fares Akram, The Seattle Times, "Hamas has developed a vast arsenal in blockaded Gaza," 25 Mar. 2019

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

15 Apr 2019

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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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).


a secret plot to overthrow a government

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