prong vs spicule

prong

noun
  • A thin, pointed, projecting part, as of an antler or a fork or similar tool. A tine. 

  • The penis. 

  • A branch; a fork. 

verb
  • To pierce or poke with, or as if with, a prong. 

spicule

noun
  • A sharp, needle-like piece. 

  • A needle-like mating structure found only in male nematodes. 

  • A tiny glass flake formed during the manufacture of glass vials 

  • A small spike of flowers. 

  • A jet of matter ejected from the photosphere of the sun. 

  • Any of many needle-like crystalline structures that provide skeletal support in marine invertebrates like sponges. 

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