Dipper vs Plough

Dipper

name

  • A Chinese constellation located near Sagittarius, one of the 28 lunar mansions and part of the larger Black Turtle. 

  • Either the Big Dipper or the Little Dipper (in the singular, chiefly the Big Dipper). 

noun

  • Of or pertaining to the Canadian New Democratic Party or supporters thereof. 

  • A member or supporter of the Canadian New Democratic Party. 

Plough

name

  • The brightest seven stars of the constellation Ursa Major. They are Alkaid, Mizar, Alioth, Megrez, Dubhe, Merak, and Phecda. 

  • A surname. 

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