Motion
MOH-shun
/ˈmoʊʃən/
The action or process of moving or being moved.
In physics, motion is described in terms of displacement, distance, velocity, acceleration, time, and speed. It's always relative to a frame of reference.
The story behind the word. The word 'Motion' traces its roots back to the Latin verb 'movere', meaning 'to move'. From 'movere' came 'motio', meaning 'a moving, a motion'. This Latin term passed into Old French as 'motion' and then into Middle English, retaining its core meaning of changing position. It's a word that perfectly captures the essence of change and dynamism.
Word relationships
- movement: Often interchangeable, but 'motion' can imply a more continuous or systematic change of position, while 'movement' can be more general or discrete.
- kinetics: Kinetics is the study of motion and its causes, not the motion itself.
- stillness: The absence of motion.
- rest: A state of not moving or being active.
Commonly confused with
- Velocity: Motion is the general act of moving; velocity is a specific measure of motion, including speed and direction.
Word family
- motional (adjective): relating to motion
- motivate (verb): to provide with a motive for action
- motor (noun): a machine that produces motion or power
Collocations
- perpetual motion
- laws of motion
- relative motion
- in motion
- range of motion
Idioms & expressions
- go through the motions
- set in motion
- make a motion
Example sentences
- "Newton's laws of motion describe how objects move under the influence of forces." Describing a fundamental physical concept.
- "The planets are in constant motion around the sun, following elliptical orbits." Observing a natural phenomenon.
- "The continuous motion of the conveyor belt ensured a steady flow of products." In a mechanical context.
Memory hook
Think of a 'MOtion' picture, which is a series of images in 'MOtion'. Moving around
When not to use
While 'motion' can refer to a formal proposal (as in 'motion to adjourn'), this is a distinct meaning from the physical concept. Ensure context clarifies.
Fun facts
- The concept of perpetual motion, a machine that could run forever without an external energy source, is a classic scientific impossibility.
- Galileo Galilei's experiments with falling objects were crucial in understanding the laws of motion.
Related words
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