motile vs mutable

motile

adj
  • In organisms: having the power to move spontaneously. 

  • In organs: having the power to move their contents, or to change their shape or tension by writhing or contracting as required by their particular physiological functions. 

  • Of or relating to those mental images that arise from the sensations of bodily movement and position. Cf. kinesthetic, proprioceptive. 

  • In organs or organelles: capable of producing motion. 

noun
  • A person whose prevailing mental imagery takes the form of inner feelings of action, such as incipient pronunciation of words, muscular innervations, etc. 

mutable

adj
  • Changeable, dynamic, evolutive; inclined to change, evolve, mutate. 

  • Having a value that is changeable during program execution. 

  • Being one of the signs Gemini, Virgo, Sagittarius and Pisces, associated with adaptability, flexibility and sympathy. 

noun
  • Something mutable; a variable or value that can change. 

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