reservoir vs substantial

reservoir

noun
  • A supply or source of something. 

  • A species that acts as host to a zoonosis when it is not causing acute illness in other susceptible species. 

  • A "black box" component that receives an input signal to be read out and mapped by another process, as part of reservoir computing. 

  • A small intercellular space, often containing resin, essential oil, or some other secreted matter. 

  • A large natural or artificial lake used as a source of water supply. 

  • A place where anything is kept in store. 

verb
  • To store or keep (something) in or as in a reservoir. 

substantial

noun
  • Anything having substance; an essential part. 

adj
  • Most important; essential. 

  • Not imaginary; real; actual; true; veritable. 

  • Having a substance; actually existing. 

  • Corporeal; material; firm. 

  • Possessed of goods or an estate; moderately wealthy. 

  • Satisfying; having sufficient substance to be nourishing or filling. 

  • Large in size, quantity, or value; ample; significant. 

  • Having good substance; strong; stout; solid; firm. 

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