neigh vs nicker

neigh

verb
  • To make a sound similar to a horse's cry. 

  • To make its cry. 

noun
  • The cry of a horse. 

nicker

verb
  • To make a soft neighing sound characteristic of a horse. 

  • To produce a snigger or suppressed laugh. 

  • To snatch or steal. 

noun
  • A type of mythological sea creature or sea monster; also, a water sprite; a nix or nixie; a mermaid or merman. 

  • Pound sterling. 

  • The cutting lip which projects downward at the edge of a boring bit and cuts a circular groove in the wood to limit the size of the hole that is bored. 

  • nigger. 

  • A snigger or suppressed laugh. 

  • Someone who nicks (steals) something, a thief. 

  • A soft neighing sound characteristic of a horse. 

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