reunify vs subdivide

reunify

verb
  • To unify again; to bring back together, or come back together, after separation. 

subdivide

verb
  • To divide into smaller sections. 

  • To divide divisions into smaller divisions. 

  • To divide a plot of land into plots for residences; to convert open land into housing. 

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