butterfly clip vs split pin

butterfly clip

noun
  • Synonym of split pin (“kind of stationery fastener”) 

  • A hairclip shaped like a butterfly, usually made from brightly colored plastic. 

split pin

noun
  • A metal fastener with two tines, the ends of which project through an object being fastened and are bent back to hold it in place. 

  • A stationery fastener that is inserted into punched holes in a stack of paper before being bent to secure them. 

How often have the words butterfly clip and split pin occurred in a corpus of books? (source: Google Ngram Viewer )