cast iron vs stiletto

cast iron

noun
  • A hard and brittle, but strong, alloy of iron, carbon, and silicon, formed by casting in a mould. 

adj
  • Inflexible or without exception. 

  • Made of cast iron. 

  • Durable; tough; resilient. 

stiletto

noun
  • A small, slender knife or dagger-like weapon intended for stabbing. 

  • An awl. 

  • A rapier. 

  • A woman's shoe with a tall, slender heel (called a stiletto heel). 

verb
  • To attack or kill with a stiletto (dagger). 

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