trajectory

[truh-jek-tuh-ree]

noun

plural

trajectories 

1. the curve described by a projectile, rocket, or the like in its flight.

2. Geometry.,  a curve or surface that cuts all the curves or surfaces of a given system at a constant angle.

trajectory

/ -trɪ, trəˈdʒɛktaɪl, trəˈdʒɛktərɪ /

noun

1. the path described by an object moving in air or space under the influence of such forces as thrust, wind resistance, and gravity, esp the curved path of a projectile

2. geometry a curve that cuts a family of curves or surfaces at a constant angle

trajectory

1. Physics,  The line or curve described by an object moving through space.

2. Mathematics,  A curve or surface that passes through a given set of points or intersects a given series of curves or surfaces at a constant angle.

Other Word Forms

• trajectile adjective
• trajection noun

Word History and Origins

Origin of trajectory¹

First recorded in 1660–70; from New Latin trājectōria, noun use of feminine of Medieval Latin trājectōrius “casting over”; equivalent to traject + -tory ¹

Example Sentences

Analysts are scrounging for any signal about the economy’s trajectory this month because the government shutdown has turned off the spigot of official government data.

Read more on The Wall Street Journal

Climate scientists say its emissions trajectory does much to influence the path of future warming for the world.

Read more on The Wall Street Journal

“The direct savings from avoiding targeted ads may not transform your finances overnight — but the behavioral shift it sparks can absolutely reshape your long-term trajectory,” he added.

Read more on MarketWatch

Yet in the absence of critical government data delayed by the ongoing federal shutdown, Wall Street is searching for any clues it can find about the trajectory of U.S. growth.

Read more on MarketWatch

But walking that path is becoming a high-wire act: If the U.S. can continue on this trajectory, the reward is high.

Read more on Barron's

Related Words

• curve 
• orbit 
• path 

When To Use

What does trajectory mean?

The trajectory of an object is the path it follows once in flight or in motion.The word is especially used in the context of the path of projectiles like rockets, but it can be used in many different contexts.The trajectory of a golf ball is the curved path it follows in the air after being hit by a golf club. The trajectory of an asteroid is the path it follows in space. The potential trajectory of a storm is the route that it may travel.In geometry, trajectory is used in a more specific way to refer to a curve that intersects through a series of points at the same angle.Example: Try to determine the trajectory of the ball as it flies through the air so you can position yourself to catch it.