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

On curved surfaces, parallel trajectories intersect—liberation movements that appear separate on maps organized around Euroamerican centers were always convergent in Afro-Asian circuits. —Anel Rakhimzhanova, Artforum, 1 Mar. 2026

On current trajectories, these economies are expected to generate only about 400 million jobs over that same period — leaving a gap of staggering proportions. —Ajaypal Banga, Twin Cities, 1 Mar. 2026

Markets, policymakers and regional leaders are now watching closely to see how far the conflict spreads, and whether the power shift in Tehran alters Iran’s political trajectory or further entrenches its security-first stance. —Garrett Downs,greg Iacurci,azhar Sukri,spriha Srivastava,emma Graham,lee Ying Shan,anniek Bao, CNBC, 1 Mar. 2026

An invitation to a local par-3 course changed the trajectory of Bennett’s life. —Edgar Thompson, The Orlando Sentinel, 1 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