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

Despite this upward trajectory, the industry faced challenges in 2024 due to adverse weather conditions, leading to heavy crop losses. —Rachel King, Forbes.com, 4 Apr. 2025

The unusual trajectory aligned the Falcon 9 with a perfectly polar orbit at an inclination of 90 degrees to the equator, bringing the four-person crew directly over the North or South Pole every 45 minutes. —ArsTechnica, 4 Apr. 2025

It was decided that that would be the trajectory, and the goal would be to kill off Van by the end of the season. —Jazz Tangcay, Variety, 4 Apr. 2025

Orbital trajectory aside, the crew members were able to lend their bodies to research, perhaps expanding knowledge of how humans can optimally live and work within the confines of a tiny spacecraft — something that may be necessary for months at a time if humans ever venture to Mars. —Jackie Wattles, CNN Money, 4 Apr. 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