trajectory

noun

tra·​jec·​to·​ry trə-ˈjek-t(ə-)rē 

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

Wall Street was singularly focused on Oracle’s forward-looking numbers and a massive growth trajectory that the company now sees thanks to its booming cloud infrastructure business and a host of new artificial intelligence deals. —Ari Levy, CNBC, 10 Sep. 2025

The presence, distribution, and motion of matter and energy through spacetime determined the curvature and evolution of that spacetime fabric, and then the curvature of that spacetime fabric determined the future trajectories and fates of every particle that exists within that spacetime. —Ethan Siegel, Big Think, 9 Sep. 2025

And that changed the trajectory of her career—and the enterprise’s results. —Bill Koch, Forbes.com, 9 Sep. 2025

The orb continued on its trajectory after the strike. —Ellen Mitchell, The Hill, 9 Sep. 2025

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

Rhymes for trajectory

• directory
• refectory
• nectary
• rectory
• subdirectory

Kids Definition

trajectory

noun

tra·​jec·​to·​ry trə-ˈjek-t(ə-)rē 

plural trajectories

: the curve that a body (as a planet in its orbit or a rocket) travels along in space