freeloading vs parasitic

freeloading

noun
  • The act of one who freeloads. 

parasitic

adj
  • Drawing upon another organism for sustenance. 

  • Exploiting another for personal gain. 

  • Of or pertaining to a biological or symbolic parasite. 

  • Of emotional damages: accompanying a physical or pecuniary injury. 

noun
  • A component of a circuit that does not show up in a circuit's schematic but does show up in the circuit's behavior. 

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