centripetal vs efferent

centripetal

adj
  • Directed towards the central nervous system; afferent. 

  • Directed or moving towards a centre. 

  • Of, relating to, or operated by centripetal force. 

efferent

adj
  • Carried outward. 

  • Carrying away from. 

noun
  • A duct or stream that carries away. 

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