Trajectory

How to spell trajectory

10 letters · 4 syllables

How to pronounce trajectory

Say the part in capitals loudest.

What does trajectory mean?

1. nounThe curved path that a moving object follows through space, such as a thrown or launched body.
2. nounThe general direction or course that something follows over time, such as a career or an economy.

Trajectory in a sentence

• The engineers calculated the trajectory of the rocket before launch.

• Her career trajectory took her from intern to director in six years.

• A sudden gust altered the trajectory of the golf ball.

• Analysts worried about the downward trajectory of the company's profits.

Where does trajectory come from?

Language of origin: Latin

Trajectory comes from the Latin verb traicere, later trajicere, which meant 'to throw across' or 'to cause to cross over'. It was formed from trans, meaning 'across', and jacere, meaning 'to throw', so the literal idea is the path traced by something hurled from one place to another. Scientists writing in Latin used the form trajectoria to describe the curve a projectile follows through space, and the word entered English in the late seventeenth century as the study of motion and ballistics developed. The same jacere root throws itself into a whole family of English words, including 'project', 'eject', 'inject' and 'reject', which all carry the sense of throwing in some direction. Knowing that hidden 'throw across' helps explain the spelling: the 'ject' in the middle is the same chunk you already write confidently in 'project'.

How the word is built

• tra- (from trans-, meaning 'across')
• ject (from jacere: to throw)
• -ory (noun suffix denoting a thing related to an action)