endogenous vs inward

endogenous

adj
  • Produced, originating or growing from within. 

  • Of a natural process: caused by factors within the body. 

inward

adj
  • Situated on the inside; that is within, inner; belonging to the inside. 

  • Not superficially obvious, inner, not expressed, especially relating to mental or spiritual faculties as opposed to external ones. 

  • Moving or tending toward the inside. 

adv
  • Towards the inside. 

  • Towards one’s mind, thoughts, or internal self. 

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