attrition vs penance

attrition

noun
  • Imperfect contrition or remorse. 

  • A gradual, natural reduction in membership or personnel, as through retirement, resignation, or death. 

  • Grinding down or wearing away by friction. 

  • The gradual reduction in a tangible or intangible resource due to causes that are passive and do not involve productive use of the resource. 

  • The loss of participants during an experiment. 

  • The wearing of teeth due to their grinding. 

  • The loss of a first or second language or a portion of that language. 

verb
  • To reduce the number of (jobs or workers) by not hiring new employees to fill positions that become vacant (often with out). 

  • To undergo a reduction in number. 

  • To grind or wear down through friction. 

penance

noun
  • A voluntary self-imposed punishment for a sinful act or wrongdoing. It may be intended to serve as reparation for the act. 

  • Any instrument of self-punishment. 

  • A sacrament in some Christian churches. 

verb
  • To impose penance; to punish. 

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