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

Right now, Wrexham are in a sweet spot, still on an upward trajectory, still surpassing their supporters’ wildest dreams and still — despite their unlikely appeal to the American market — a team so intimately connected to their town and the fans on their doorstep. —Oliver Kay, New York Times, 8 Mar. 2026

Hence, SpaceX can’t be valued on its current profits, but only on its prospects from gigantic growth in the most pioneering of industries whose future trajectory is also unknowable. —Shawn Tully, Fortune, 8 Mar. 2026

The number one doesn't really show up in polling, and that's where the people of Florida want our state to remain on the trajectory that it's been going. —March 8, CBS News, 8 Mar. 2026

Just as the two relationships are marked by different trajectories, Diana and Camilla’s engagement rings couldn’t be more different. —Rachel Burchfield, InStyle, 7 Mar. 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