mortgage vs undertake

mortgage

verb
  • To pledge and make liable; to make subject to obligation; to achieve an immediate result by paying for it in the long term. 

  • To borrow against a property, to obtain a loan for another purpose by giving away the right of seizure to the lender over a fixed property such as a house or piece of land; to pledge a property in order to get a loan. 

noun
  • A special form of secured loan where the purpose of the loan must be specified to the lender, to purchase assets that must be fixed (not movable) property, such as a house or piece of farm land. The assets are registered as the legal property of the borrower but the lender can seize them and dispose of them if they are not satisfied with the manner in which the repayment of the loan is conducted by the borrower. Once the loan is fully repaid, the lender loses this right of seizure and the assets are then deemed to be unencumbered. 

undertake

verb
  • To commit oneself (to an obligation, activity etc.). 

  • To pass a slower moving vehicle on the curbside rather than on the side closest to oncoming traffic. 

  • To take upon oneself; to start, to embark on (a specific task etc.). 

noun
  • The passing of slower traffic on the curbside rather than on the side closest to oncoming traffic. 

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