subsection vs tranche

subsection

noun
  • A defined part of a section. 

  • An informal taxonomic category below section and above family. 

  • A subpart of a legal document such as law. 

  • A taxonomic rank below the section, but above the species. 

verb
  • To insert subsections (into some text, etc.). 

tranche

noun
  • A slice, section or portion. 

  • A distinct subdivision of a single policyholder's benefits, typically relating to separate premium increments. 

  • One of a set of classes or risk maturities that compose a multiple-class security, such as a CMO or REMIC; a class of bonds. Collateralized mortgage obligations are structured with several tranches of bonds that have various maturities. 

  • A pension scheme's or scheme member's benefits relating to distinct accrual periods with different rules. 

verb
  • To divide into tranches. 

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