subsection vs tributary

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.). 

tributary

adj
  • Related to the paying of tribute. 

  • Yielding supplies of any kind; serving to form or make up, a greater object of the same kind, as a part, branch, etc.; contributing. 

  • subordinate; inferior 

noun
  • A nation, state, or other entity that pays tribute. 

  • A natural water stream that flows into a larger river or other body of water. 

  • A vein which drains into a another vein. 

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