trajectory

Everyday

1. A trajectory is the curved path that a thrown, kicked or fired object follows through the air or space. tree →
2. A trajectory is also the direction in which something develops over time, like the trajectory of a career or of prices. tree →

In the lessons

In science and maths it is the path of a ball, arrow or rocket, usually an arch shape called a parabola because gravity pulls it down. In space lessons rockets and probes follow trajectories to planets. In grown-up talk: «on an upward trajectory» means getting better or bigger. Phrases: «the ball's trajectory», «change trajectory», «on a trajectory».

Examples

• The football followed a high trajectory into the net. tree →
• Scientists worked out the rocket's trajectory to Mars. tree →
• Gravity bends a ball's trajectory into a curve. tree →
• The arrow's trajectory was too low and it hit the ground. tree →
• Draw the trajectory of the paper plane on the graph. tree →
• The team's results are on an upward trajectory. tree →
• A strong wind changed the kite's trajectory. tree →

Note

Countable; plural «trajectories» (y → ies). Stress on «-JEC-». A trajectory is a path, not a speed. A thrown ball's path is a curve (a parabola), not a straight line, because gravity pulls it down all the time.