susceptibility vs urge to merge

susceptibility

noun
  • emotional sensitivity. 

  • the condition of being susceptible; vulnerability 

  • Being vulnerable to a treatment (usually an antibiotic or antifungal); also, the degree of such vulnerability (i.e., weak, moderate, or strong). 

  • electric susceptibility, a measure of how easily a dielectric polarizes in response to an external electric field (compare permittivity). 

urge to merge

noun
  • A strong desire to form intense emotional connections, stereotypically associated with lesbians. 

How often have the words susceptibility and urge to merge occurred in a corpus of books? (source: Google Ngram Viewer )