trajectory

noun

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

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
At this historic inflection point, the trajectory of American democracy may well determine the trajectory of democracy around the world. Charles A. Kupchan, The Atlantic, 10 Jan. 2025 The outcome of these negotiations could shape the trajectory of the conflict and its broader regional implications. Daniel R. Depetris, Newsweek, 10 Jan. 2025 On the program's current trajectory, Fox said NASA would be able to choose a new MSR architecture in mid-2026. Stephen Clark, Ars Technica, 8 Jan. 2025 Those will either keep rates on an upward trajectory or, perhaps, change the trend for the new year. Diana Olick, CNBC, 8 Jan. 2025 See all Example Sentences for trajectory 

Word History

Etymology

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

First Known Use

1696, in the meaning defined at sense 1

Time Traveler
The first known use of trajectory was in 1696

Dictionary Entries Near trajectory

Cite this Entry

“Trajectory.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/trajectory. Accessed 18 Jan. 2025.

Kids Definition

trajectory

noun
tra·​jec·​to·​ry trə-ˈjek-t(ə-)rē How to pronounce trajectory (audio)
plural trajectories
: the curve that a body (as a planet in its orbit or a rocket) travels along in space
Last Updated: - Updated example sentences
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