motile vs on wheels

motile

adj
  • 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. 

  • In organisms: having the power to move spontaneously. 

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

on wheels

prep
  • Used other than figuratively or idiomatically: see on, wheels. (Having wheels affixed to the bottom, and so transportable; synonym of wheeled). 

  • Mobile; able to be moved; especially, synonym of on the move. 

  • To a large degree, excessively. 

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