duct vs outflow

duct

noun
  • a pipe, tube or canal which carries gas or liquid from one place to another 

  • a vessel for conveying lymph or glandular secretions such as tears or bile 

  • a tube or elongated cavity (such as a xylem vessel) for conveying water, sap, or air 

  • a layer (as in the atmosphere or the ocean) which occurs under usually abnormal conditions and in which radio or sound waves are confined to a restricted path 

  • an enclosure or channel for electrical cable runs, telephone cables, or other conductors 

verb
  • to enclose in a duct 

  • to channel something (such as a gas) or propagate something (such as radio waves) through a duct or series of ducts 

outflow

noun
  • A fluid that flows out. 

  • Any outward movement. 

  • Something that flows out of a sewage treatment plant. 

  • The process of flowing out. 

  • A stream of gaseous material emanating from an active galactic nucleus. 

  • The part of a system that allows material to flow out. 

verb
  • To flow outward. 

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