hummock vs lapwing

hummock

noun
  • A fistful. 

  • A ridge or hill of ice in an ice field. 

  • A small hill; a hillock; a knoll. 

lapwing

noun
  • A silly man. 

  • The northern lapwing (Vanellus vanellus). 

  • Any of several medium-sized wading birds belonging to the subfamily Vanellinae, within family Charadriidae. 

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