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

the trajectory of a missile

2

: a path, progression, or line of development resembling a physical trajectory

an upward career trajectory

the nation's economic 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

Other states could soon follow — including New York, which is pondering a similar bill — in a domino effect that could completely derail the automaker’s current trajectory. — Victor Tangermann, Futurism, 9 July 2026

This lofty standard of play clearly doesn’t scare Belgium, which is on a surging trajectory of its own heading into the teams’ World Cup quarterfinal match on Friday. — ABC News, 9 July 2026

The collaboration builds on several NVIDIA resources already available through LeRobot, including an open-source physical AI dataset containing more than 350,000 real and simulated robot trajectories and 57 million grasp examples. — Jijo Malayil, Interesting Engineering, 9 July 2026

Two new surveys suggest Georgia’s marquee statewide races are following different trajectories. — Adam Beam, AJC.com, 9 July 2026

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