ferrule vs ruler

ferrule

noun
  • The pinched metal band which holds the bristles of a paintbrush to the shaft. 

  • The plastic band attaching the tip to the cue. 

  • The metal spike at the end of the shaft of an ice axe. 

  • A band or cap (usually metal) placed around a shaft to reinforce it or to prevent splitting. 

  • A bushing for securing a pipe joint. 

  • A metal sleeve placed inside a gutter at the top. 

verb
  • To equip with a ferrule. 

ruler

noun
  • A (usually rigid), flat, rectangular measuring or drawing device with graduations in units of measurement; a straightedge with markings. 

  • A person who rules or governs; someone or something that exercises dominion or controlling power over others. 

verb
  • To beat with a ruler (as a traditional school punishment). 

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