concentrate vs propagate

concentrate

verb
  • To approach or meet in a common center; to consolidate. 

  • To focus one's thought or attention (on). 

  • To increase the strength and diminish the bulk of, as of a liquid or an ore; to intensify, by getting rid of useless material; to condense. 

  • To bring to, or direct toward, a common center; to unite more closely; to gather into one body, mass, or force. 

noun
  • A substance that is in a condensed form. 

propagate

verb
  • To spread from person to person; to extend the knowledge of; to originate and spread; to carry from place to place; to disseminate. 

  • To cause to take effect on all relevant devices in a network. 

  • To produce young; to be produced or multiplied by generation, or by new shoots or plants. 

  • To cause to spread to extend; to impel or continue forward in space. 

  • To cause to continue or multiply by generation, or successive production. 

  • To generate; to produce. 

  • To take effect on all relevant devices in a network. 

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