Definition of trajectory in English:

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Pronunciation: /trəˈdʒɛkt(ə)ri/
Pronunciation: /ˈtradʒɪkt(ə)ri/

noun (plural trajectories)

1The path followed by a projectile flying or an object moving under the action of given forces: the missile’s trajectory was preset figurative the rapid upward trajectory of Rich’s career
More example sentences
  • As supply meets demand, a future is created, independent of any plan, but revealed in the trajectories of market forces.
  • Mortars are ballistic weapons that have projectile trajectories undistorted by rocket engine or guidance system.
  • Suborbital paths are the trajectories of choice for ballistic missiles.
course, route, path, track, line, orbit, flight, flight path, ambit, direction, bearing, orientation, way, tack, approach
2 Geometry A curve or surface cutting a family of curves or surfaces at a constant angle.
Example sentences
  • These three trajectories are known as conic sections, as they are also the curves produced by cutting a cone along different planes.
  • The thick line is a calculated trajectory near a surface and the thin line is a trajectory far from any surface.
  • To investigate this possibility, a simple system can be designed to generate drip trajectories where the degree of chaos can be tuned.


Late 17th century: from modern Latin trajectoria (feminine), from Latin traject- 'thrown across', from the verb traicere, from trans- 'across' + jacere 'to throw'.

  • jet from late 16th century:

    The name jet for a hard black semi-precious mineral comes ultimately from the Greek word gagatēs ‘from Gagai’, a town in Asia Minor. When we refer to a jet of water or gas, or a jet aircraft, we are using a quite different word. It comes from a late 16th-century verb meaning ‘to jut out’, from French jeter ‘to throw’, which goes back to the Latin jacere ‘to throw’. Jut (mid 16th century) is a variant of jet in this sense. Jacere is found in a large number of English words including abject (Late Middle English) literally ‘thrown away’; conjecture (Late Middle English) ‘throw together’; deject (Late Middle English) ‘thrown down’; ejaculate (late 16th century) from jaculum ‘dart, something thrown’; eject (Late Middle English) ‘throw out’; inject (late 16th century) ‘throw in’; jetty (Late Middle English) something thrown out into the water; project (Late Middle English) ‘throw forth’; subject (Middle English) ‘thrown under’; trajectory (late 17th century) ‘something thrown across’. Especially if you use budget airlines, air travel today is far from glamorous, but in the 1950s the idea of flying abroad by jet aircraft was new and sophisticated. At the start of that decade people who flew for pleasure came to be known as the jet set.

Words that rhyme with trajectory

directory, ex-directory, interjectory, rectory, refectory

For editors and proofreaders

Line breaks: tra|jec¦tory

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