1
the trajectory of sth
trajectory 常与 of 连用，说明运动物体或路径的主体。
The trajectory of the rocket was tracked by radar.
火箭的轨道由雷达跟踪。
轨道；弹道；轨线
trajectories — plural of trajectory
先理解核心含义，再看它在真实句子里的用法。
轨道；弹道；轨线
the path followed by an object moving through space
The trajectory of the rocket was tracked by radar.
火箭的轨道由雷达跟踪。
物体运动所经过的路径。
The path an object takes as it moves.
物体在空间中移动的路径
the path followed by an object moving through space
物体在空间中运动的轨迹。
The path of a body as it travels through space.
动力系统随时间演变所经历的一系列中间状态的有序集合
The ordered set of intermediate states assumed by a dynamical system as a result of time evolution.
Mission control tracked the rocket's trajectory until it reached orbit.
任务控制中心追踪火箭的飞行轨迹，直到它进入轨道。
Engineers calculated the ball's trajectory to predict where it would land.
工程师们计算了球的轨迹，以预测它会落在哪里。
We watched the trajectory of the falling leaves as they drifted to the ground.
我们看着落叶飘向地面时的运动轨迹。
trajectory 常与 of 连用，说明运动物体或路径的主体。
The trajectory of the rocket was tracked by radar.
火箭的轨道由雷达跟踪。
follow 在此表示“沿着……行进”，与 trajectory 搭配指沿某路径运动。
The missile followed a curved trajectory.
导弹沿曲线弹道飞行。
on a trajectory 后常接 toward/into 等介词短语，表示运动方向。
The spacecraft is on a trajectory toward Mars.
航天器正处在前往火星的轨道上。
Not this
The missile's orbit was tracked by radar.
Use this
The missile's trajectory was tracked by radar.
orbit 指天体环绕另一天体运行的闭合轨道，trajectory 指飞行物在空中经过的路径；导弹的飞行路径不是环绕运行，因此应改用 trajectory。
Not this
The missile follows high trajectory.
Use this
The missile follows a high trajectory.
trajectory 是可数名词，单数形式前需要冠词 a/an；汉语没有冠词，所以容易漏掉，这里应在 high trajectory 前加 a。
Not this
The spacecraft is in a trajectory to Mars.
Use this
The spacecraft is on a trajectory to Mars.
表示“处于某条飞行路径上”时，trajectory 与介词 on 搭配；in orbit（在轨道上）的说法会误导学习者误用 in。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
弹道轨迹
The missile followed a high ballistic trajectory before re-entering the atmosphere.
导弹在重新进入大气层之前沿着高弹道轨迹飞行。
飞行轨迹
Air traffic controllers monitor each aircraft's flight trajectory.
空中交通管制员监控每架飞机的飞行轨迹。
抛射体的轨迹
Students calculated the trajectory of a projectile in the physics lab.
学生们在物理实验室计算抛射体的轨迹。
弯曲的轨迹
The planet follows a curved trajectory around the star.
这颗行星围绕恒星沿弯曲的轨迹运行。
轨迹计算
The engineers performed a trajectory calculation for the space probe.
工程师们对太空探测器进行了轨迹计算。
改变轨迹
The spacecraft fired its thrusters to change trajectory.
航天器点燃推进器以改变轨迹。
处于上升轨道/呈上升趋势
After the new policy, the company's profits are on an upward trajectory.
新政策实施后，公司利润呈上升趋势。
职业发展轨迹
Her career trajectory took off after she joined the research team.
加入研究团队后，她的职业发展轨迹突飞猛进。
改变某事物的轨迹/方向
Meeting her mentor changed the trajectory of his life.
遇到她的导师改变了他的人生轨迹。
Use trajectories naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
联想：一颗炮弹飞出的弧线，trajectory 就是它经过的轨道/弹道。
语域：mixed 常见场景：physics、aerospace/ballistics、figurative business or career talk 本义指物体在空间中行经的路径，通常出现在物理、航天、弹道等比较正式的科技语境；也常见于商业或职业讨论中的比喻用法（如“发展轨迹”）。正式程度随语境变化，日常口语中较少直接用这个词。
Directory 与 trajectory 在美式发音中押韵（重音都在第二个音节，/ɛktɚi/ 相同）。factory、territory、victory、category 虽然拼写相似，但重音多在第一个音节，且元音不同，所以不押韵。
Dictionary facts from ECDICT, WIKTIONARY.