busk vs sustain

busk

verb
  • To solicit money by entertaining the public in the street or in public transport. 

  • To tack, cruise about. 

noun
  • A strip of metal, whalebone, wood, or other material, worn in the front of a corset to stiffen it. 

  • A corset. 

sustain

verb
  • To encourage or sanction (something). 

  • To provide for or nourish. 

  • To maintain, or keep in existence. 

  • To allow, accept, or admit (e.g. an objection or motion) as valid. 

  • To keep from falling; to bear; to uphold; to support. 

  • To confirm, prove, or corroborate; to uphold. 

  • To aid, comfort, or relieve; to vindicate. 

  • To experience or suffer (an injury, etc.). 

noun
  • A mechanism which can be used to hold a note, as the right pedal on a piano. 

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