aid vs relieve

aid

verb
  • To provide support to; to further the progress of; to help; to assist. 

  • To climb with the use of aids such as pitons. 

noun
  • Help; assistance; succor, relief. 

  • An historical subsidy granted to the crown by Parliament for an extraordinary purpose, such as a war effort. 

  • A helper; an assistant. 

  • An exchequer loan. 

  • Something which helps; a material source of help. 

  • A pecuniary tribute paid by a vassal to his feudal lord on special occasions. 

  • The rider's use of hands, legs, voice, etc. to control the horse. 

relieve

verb
  • To provide comfort or assistance to (someone in need, especially in poverty). 

  • To ease (someone, a part of the body etc.) or give relief from physical pain or discomfort. 

  • To ease (a person, person's thoughts etc.) from mental distress; to stop (someone) feeling anxious or worried, to alleviate the distress of. 

  • To release (someone) from or of a difficulty, unwanted task, responsibility etc. 

  • To free (someone) from debt or legal obligations; to give legal relief to. 

  • To alleviate (pain, distress, mental discomfort etc.). 

  • To urinate or defecate. 

  • To ease one's own desire to orgasm, often through masturbation to orgasm. 

  • To bring military help to (a besieged town); to lift the siege on. 

  • To free (someone) from their post, task etc. by taking their place. 

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