inertia vs motion

inertia

noun
  • Lack of activity; sluggishness; said especially of the uterus, when, in labour, its contractions have nearly or wholly ceased. 

  • In a person, unwillingness to take action. 

  • The property of a body that resists any change to its uniform motion; equivalent to its mass. 

motion

noun
  • A change from one place to another. 

  • A movement of the bowels; the product of such movement. 

  • A state of progression from one place to another. 

  • from κίνησις (kinesis); any change. Traditionally of four types: generation and corruption, alteration, augmentation and diminution, and change of place. 

  • A formal request, oral or written, made to a judge or court of law to obtain an official court ruling or order for a legal action to be taken by, or on behalf of, the movant. 

  • A change of position with respect to time. 

  • A parliamentary action to propose something. A similar procedure in any official or business meeting. 

  • A piece of moving mechanism, such as on a steam locomotive. 

  • Movement of the mind, desires, or passions; mental act, or impulse to any action; internal activity. 

  • Change of pitch in successive sounds, whether in the same part or in groups of parts. (Conjunct motion is that by single degrees of the scale. Contrary motion is when parts move in opposite directions. Disjunct motion is motion by skips. Oblique motion is when one part is stationary while another moves. Similar or direct motion is when parts move in the same direction.) 

verb
  • To introduce a motion in parliamentary procedure. 

  • To make a proposal; to offer plans. 

  • To gesture indicating a desired movement. 

How often have the words inertia and motion occurred in a corpus of books? (source: Google Ngram Viewer )