chin strip vs chinstrap

chin strip

noun
  • Synonym of chinstrap (“type of beard”) 

chinstrap

noun
  • A form of beard that follows the jawline but does not cover the rest of the chin. 

  • A strip of leather or material used to fasten a hat or helmet under the chin. 

  • A band of colour below a bird's mouth, resembling the chinstrap of a helmet. 

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