pinhead vs spider monkey

pinhead

noun
  • A human head that is unusually tapered or small, often due to microcephaly, or a person with that trait. Often promoted in freak shows as "human pinheads". 

  • A foolish or stupid person. 

  • The head of a pin. (Frequently used in size comparisons.) 

  • A telemark skier. 

  • A newborn cricket used as food for pets. 

  • The immature juvenile fruiting body of a mushroom prior to its gills opening. 

spider monkey

noun
  • Any New World monkey of the genus Ateles, with long, spindly limbs. 

  • A muriqui, New World monkey of the genus Brachyteles, closely related to Ateles. 

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