on the order of vs undifferentiated

on the order of

adv
  • Approximately. 

prep
  • In the manner of; along the lines of; like; of a similar kind to; more-or-less equivalent to. 

undifferentiated

adj
  • describes a plant body where the vascular tissue has not developed, as in the thallophytes 

  • Not differentiated, not different, alike 

  • describes tissues where the individual cells have not yet developed mature or distinguishing features, or describes embryonic organisms where the organs cannot be identified. 

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